Casio fx-CG50 User manual

Getting Started with the fx-CG50
Your calculator can complete a huge variety of operations.
This guide will help you to get started with
Graphs, Calculations, Statistics and Equations.
It is especially aimed at A-level Mathematics.

Page | 2
Choosing your mode
From the main menu you can select various options which will take you to screens where you can
perform calculations
work with statistics
plot graphs
solve equations
and much more. The most useful menus to start learning the calculator for Maths are
Use this mode for arithmetic calculations, function calculations, binary, octal, decimal, and
hexadecimal calculations, matrix and vector calculations.
Use this mode to perform single-variable and paired-variable statistical calculations, to perform
tests, to analyse data and to draw statistical graphs.
Use this mode to store graph functions, plot and analyse the functions.
Use this mode to solve linear equations with two to six unknowns, and polynomials from 2nd to
6th degree.
Some important keys NOT found on your scientific calculator
Many of the general features are very similar to your scientific calculator. So for most things, just try looking for the
key you would usually use.
lOne basic difference is that the “=” key is replaced with an “EXE” key. This stands for “execute”, and is
what you press to actually complete most actions on the calculator.
pAllows you to change between screens. For example to go from plotting a graph to solving an equation
or just completing a calculation, you would go via the main menu.
dThis is like your “back” button. If you want to go back to where you were previously, this will take you
there.
iAllows you to access a whole range of different options. If you can’t find something, this is often a
good place to start looking!
Always keep an eye on the bottom of the screen as there will often be a list of things that you can do there. You can
choose these options by pressing one of keys qto u, which lines up below the choice you want to make.
Some advice
We strongly recommend that you reset the calculator before learning about it. Please see page 12 for more
information.
You can’t break the calculator! At least, not by using it. If you get stuck, try a different menu or the ikey.
There’s plenty of support from Casio –please see the back page.

Page | 3
Graphs [Option 5]
Plotting graphs –basics
Type the equations of the graphs that you would like to
plot…
Hint: you can change between types of graphs by
pressing eon this screen, and this will allow you to plot
parametric curves if you need to.
…then press uto see the drawing of the graphs
View window
If the scale on your graph is just far too big or small for you to see what you need, then you can change the view
window manually.
V-Window –press Le and this will take you to a screen where you can change what you can see
your graph. You can alter the range of xand yvalues that you can see on the screen, the scale, and the
grid. From the graph screen, eqd will reset the view window to the original settings.
If the grid isn’t showing, then you will need to adjust either or both of the following
othe scale is too fine (too many marks on the axis) or too coarse (no marks show on the axis)
othe grid is not set to LINE (Lp(SETUP) and scroll to GRID).
You can also move around your graph. You can try
Zoom –press +or -when you are looking at your graph, and this will zoom in or out, based on the
scale settings (Lw(ZOOM),then w). Lwy will “auto” zoom so will often give a sensible scale.
Move –press !or $when you are looking at your graph, and this will move the view left or right.
Pan –if you need to move a long way it is quicker to use pan. Press iw to get into the pan mode. Then
use the four-way arrow button to scroll to where you want to pan from. Press lto select that position,
scroll again to move the graph around, and when you have the position you want, press lagain and then
dto get out of pan mode.
Trace –you can move along a graph by pressing Lq. Move along a graph by using the cursor !$.
Move between graphs using the cursor BN. Move to a specific coordinate by entering an x-value.

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Once you have the plot of your graph(s) there are a number of useful features that you can take advantage of …
Feature
Useful for…
Steps / key presses
Screen
If you need to sketch an
inverse function, or find
the range or domain of
the inverse function.
Hint: Check the domain
is valid for the inverse,
and that the inverse is
not one-many or
many-many.
Press Lr to get the
function, then choose ragain
for INVERSE. If you have more
than one graph plotted, choose
the one you want by using the
BN keys, then l
Here is the inverse of the blue
graph, plotted in green…
Checking the
roots/solutions of an
equation.
Press Ly to get the
function, and then choose q
for ROOT.
Select which curve you want the
roots of, then use !and $to
switch between roots if there are
more than one.
Checking the coordinates
of maximum and
minimum points of a
curve.
Press Ly to get the
function, and then choose w
for MAX or efor MIN.
Select which curve you want the
max or min of, then use !and
$to switch between stationary
points if there is more than one.
Checking the coordinates
of points of intersection
between two curves.
Press Ly to get the
function, and then choose y
for INTERSECT.
Use !and $to switch
between points of intersection if
there is more than one, and press
lif you want to see the
coordinate point labelled on the
graph.
Checking the
corresponding yor x
value when finding
coordinates of points
that are on the curve.
Press Ly to get the
function, and then choose uto
go to the next page. Then choose
qfor Y-CAL and choose wfor
X-CAL.
Select which curve you want a
value from, then type in the
value you want.
This was to find the y-value when x
was equal to 2.25

Page | 5
Feature
Useful for…
Steps / key presses
Screen
Checking the area under
a curve, or the area
between a curve and a
line
Press Ly to get the
function, and then choose u
to go to the next page. Then
choose efor the integral.
Within this you can choose
which gives the area
under a curve between any
limits that you choose yourself
which gives the area
under the curve between the
roots of the function
which gives the area
between a line and a curve
Area under a curve between two
limits:
Area under a curve between two
roots of the equation:
Area between a line and a curve:
Draw a tangent to a
curve.
Hint: to show the value
of the derivative (the
gradient), use SETUP
(Lw) and scroll to
DERIVATIVE, then choose
ON.
Press Lrto enter the
function, and then
choose w.
Use the scroll cursor !$ to
move the tangent, or enter a
x-value for a specific coordinate.
Hint: Press lto see the
equation of the tangent.

Page | 6
Run-Matrix (Calculations) [Option 1]
Changing the mode for calculations
Once you have reset your calculator most things will be automatically set up how you need them.
If you are doing a calculation and you do need to change between degrees and radians mode, for example, you can
do this by pressing Lp which takes you to the SETUP screen. Scroll down to find the ANGLE option and you
can choose degrees or radians here.
Feature
Useful for…
Steps / key presses
Screen
Typing in logarithms
which are not base 10.
Go to the menu by
pressing r, and then press w
Typing in modulus
functions.
Go to the menu by
pressing r, and then press e
Checking answers if you
have to find “the value of

 when x =…”
Go to the menu by
pressing r, and then press r
again
Checking answers if you
have to find “the value of

when x=…”
Go to the menu by
pressing r, and then press y
Checking answers for
definite integration (with
limits).
Go to the menu by
pressing r, and then press u
to go to the next page of options,
the select the integral function by
pressing q
Checking answers if you
are working out the sum
to nterms of a series.
Go to the menu by
pressing r, and then press u
to go to the next page of options,
the select the “sum” function by
pressing w
Checking solutions to
quadratics, cubics, trig
Press ir to get into the
menu. From here press
Solving a quadratic example

Page | 7
Feature
Useful for…
Steps / key presses
Screen
equations, exponential
and logarithmic
equations, modulus
equations, etc.
Hint: if you want an
exact value when solving
a quadratic or cubic, you
will be much better using
the “Polynomial”
function in the
“Equation” menu, as this
will give you your
solutions in both decimal
and surd form.
yto get into mode.
From here you can type in the
equation you want to solve, using
L.to get an = symbol when
you need it.
For trig equations you can specify
your interval. After typing your
equation, type,f,
minimum value ,maximum
value kbefore pressing lto
get your solutions. Make sure you
are in the correct mode (radians
or degrees).
Solving a trig equation example:
“Solve    ,     ”
Type in the equation to be solved
and the region…
and press lfor the solutions…
True/False
Checking work on
algebraic fractions
(simplifying, adding,
writing as partial
fractions, changing
improper to mixed).
Checking that you have
simplified a logarithmic
or exponential equation
correctly.
Checking that you have
simplified using trig
identities correctly, or
just checking that you
memorised a trig identity
correctly.
Type what you started with on
the LHS, an “=” in the middle (by
typing L. to get the “=”
remember!) and what you
finished with on the RHS.
When you press lthe
calculator will give a value of…
1 if what you typed is TRUE
0 if what you typed is FALSE.
Confirming that these are
simplified correctly…
Hint: BEFORE USING THIS, make sure that you define xas an
appropriate value. For example, if xis set to equal 0, it will tell
you that
23xx
is TRUE (clearly not true for all real values
of x)!
Make sure you choose an appropriate value for xfor the
identity or equation that you are checking. To do this, type the
value you want to use for x, then press bfl. This will
assign that value to x.
Confirming that this identity is
NOT correct…

Page | 8
Statistics [Option 2]
Data are stored in lists. From these, you can calculate statistics such as mean and standard deviation.
Feature
Useful for…
Steps / key presses
Screen
Typing in the data. Enter
the data line by line,
pressing lafter each
item.
Hint: you can type a label
for the data in the cell
below the List number.
Enter the data line by line,
pressing lafter each item.
Telling the calculator
which list(s) to use for
calculations.
For 1-variable statistics
set 1-Var lists.
For 2-variable statistics
(regression), set 2-Var
lists.
Press wto enter mode,
then uand scroll to the 1-Var or
2-Var lists.
XLIST is the list of values. Press
to change the List
number.
YLIST is the 2nd list of values for
2-variable data.
FREQ is the frequency of each
data item. This is either 1 or a list
of frequencies. Press to
specify frequencies in a list.
Calculating statistics of a
single variable, for
example mean or
standard deviation.
Hint: BEFORE USING THIS
make sure that you have
told the calculator which
list to use (see )
Press wto enter mode,
then q
Hint: use Nto scroll down for
more statistics such as quartiles
Calculate regression
statistics (equation of the
regression line and the
correlation coefficient)
Press to enter the
statistics calculation menu, then
e( ).
This will give you a choice of
regression types.
Choose q( ) for linear
regression and then w( )
for the equation type.

Page | 9
You can draw graphs from the lists of data using (q)
Feature
Useful for…
Steps / key presses
Screen
Telling the calculator
what type of graph and
which list(s) to use.
The settings depend on
the type of graph –see
examples below.
Hint: you can set 3 graphs
From the statistics menu press
q( ) then u( ).
Choose which graph number you
wish to set (q,w,e).
Press dto return to the graph
screen.
Scatter
Draw a SCATTER GRAPH.
Use above and
the following setttings:
GRAPH TYPE: Scatter
(q)
XLIST: List number with
your 1st set of values
YLIST: List number with
your 2nd set of values
FREQUENCY: 1 or List of
frequencies
The other settings allow
you to set colours and
mark type.
From the graph screen press the
key for your graph in SET
You can draw the regression line
(line of best fit). From the graph
plot, press qwwu for a
linear regression.
MedBox
Draw a BOX PLOT
Use above and
the following setttings:
Graph Type: MedBox
(uw)
XList: List number with
your values
Frequency: 1 or List of
frequencies
Outliers: Off (default) or
On
The other settings allow
you to set colours.
From the graph screen press the
key for your graph created in SET.
Hint: You can find the values of
each quartile by pressing
Lq(TRACE) and using the
cursor !$
Hist
Draw a HISTOGRAM.
Use above and
the following setttings:
GRAPH TYPE: Hist
(uq)
XLIST: List number with
your values
FREQUENCY: 1 or List of
frequencies
The other settings allow
you to set colours.
From the graph screen press the
key for your graph created in SET.
Enter the START value (the lowest
value for the graph to start) and
the WIDTH of each interval. Then
press l

Page | 10
Equations [Option A]
Simultaneous linear equations
The equation has to be entered in the form
ax by c
(2 unknowns) or
ax by cz d  
(3 unknowns), and
similarly for more unknowns. Don’t forget to rearrange your equation if it is not in this form.
Feature
Useful for…
Steps / key presses
Screen
Find the solutions of the
equations.
Hint: If the lines (2 unknowns) or
planes (3 unknowns) are parallel,
the calculator will show ‘No
Solution’. If the lines or planes
are coincident (lie on each other)
it will show ‘Infinite Solutions’).
From the EQUATION
menu, press qto
choose the menu,
then choose the number
of unknowns.
Press q
Notice that the exact value is given
on the bottom right
Polynomial equations
The equations must be in the form
20ax bx c  
for quadratics and
32 0ax bx cx d   
for cubics.
Remember to rearrange your equation if necessary.
Feature
Useful for…
Steps / key presses
Screen
Find the solutions of the
equations.
Hint 1: If the equation does not
have one of the terms, enter 0
for the coefficient e.g. for
32 4 0xx  
enter
Hint 2: If the display shows ‘No
Real Solutions’or a solution such
32i
, see below.
From the EQUATION
menu press wto
choose the menu
then the degree (e.g. 2
for quadratics, 3 for
cubics).
Enter the coefficients of
your equations.
Press q
Notice that the exact value is given
on the bottom right

Page | 11
If the quadratic equation has no real solutions, or a cubic has only 1 real solution, then the calculator will show the
result depending on how it is set up.
Type
Screen
Explanation
How to change
Quadratic
The graph lies entirely
above the x-axis.
To show complex roots, press d.
Enter SETUP by pressing Lp
and scroll to Complex Mode, then
choose the appropriate notation
(wor e).
Quadratic
The graph lies entirely
above the x-axis.
Complex roots are
shown.
To show real roots only, press
d. Enter SETUP by pressing
Lp. Scroll to Complex Mode,
then press q.
Cubic
The function has complex
roots.
To show real roots only, press
d. Enter SETUP by pressing
Lp. Scroll to Complex Mode,
then press q.
Cubic
The graph only crosses
the x-axis once.
To show complex roots, press d.
Enter SETUP by pressing Lp
and scroll to Complex Mode, then
choose the appropriate notation
(wor e).

Page | 12
Resetting the calculator
From the main menu, choose System (Option G)
Choose RESET (y), then MAIN (w). You will be asked to confirm. Press q.
Return to the main menu.
Taking it further
This guide has introduced you to some of the common uses of the fx-CG50 in Maths A-level. There are many other
things you can do.
Follow the on-screen menus to explore. Some menus have more options indicated by
a black background (for example )
an arrow
More menus can usually be found by pressing the ikey.
You can access stored values of variables from statistics, graphs and probability distributions by pressing the o
key.
The calculator can undertake a huge variety of maths. Now you have tried the basic functions, take a look at these
Use this mode to calculate probabilities from many distributions, and graph the normal
distribution.
Use this mode to store functions, to generate a table of values, and to draw graphs.
Use this mode to store recursion formulas, to generate a table of values, and to draw graphs.
Use this mode to draw graphs of conic sections.
Use this mode to plot and analyse 3-dimensional graphs.
You can explore much more sophisticated maths and ways of using the calculator in the manual.
Casio have many videos, lesson resources and skills sheets. Take a look at our dedicated education website
https://education.casio.co.uk/
Casio gratefully thanks Kim Ogden for substantial contributions to this guide. We hope that you enjoy using the
calculator.