To work out 5 x 3 + 2 you should enter:
532
which will give 17 as your answer.

What about 2 + 5 x 3 ? This could mean 2 + 15 = 17 or it could mean 7 x 3 = 21. Brackets are needed to clarify the calculation. (2 + 5) x 3 is entered as:
253

To work out you should enter:
5.26.11.47.84.28.9
and you will get 23.2525627

Or +/-. Be clear about the difference between this button and the "take away" button. In a calculation like 6 - -7 the first - means "take away" and the second means "negative 7".
You should enter 67 to get 13 as your answer.

Or x^y. You use this to work out powers or indices. To work out 3⁴, enter 34 and you will get 81. For 2⁶ enter 26, which is 64. For 5^-1 you should enter 51 and get 0.2.
What is 6⁰?

You can add, subtract, multiply and divide fractions with this button, and simplify fractions and convert between decimal and fraction form.
To work out you should enter 2534 and your calculator should display 1320 which means . If you press again the calculator will convert this fraction to the decimal 1.15.
You can convert any decimal to a fraction with this button. To convert 0.126 you enter 0.126 and 63500 is displayed.

The area of a trapezium is given by the formula . When a = 3 , b = 4 and h = 7, enter
12347
and your calculator will display 24.5.

Or EE button. Use this to enter numbers in standard form. For example, the number 6 x 10¹³ is entered as 613.
So to work out 4.1 x 10⁹ + 3.8 x 10⁸ you enter
4.193.88 to obtain the answer 4.48 x 10⁹

Many calculators now have an ANS buttons as well as an "=" button. The ANS button will recall the previous answer. These buttons can be used to repeat simple calculations over and over again (which is called iteration). For example, if this set of instructions is entered:
1223
then 9, 7.5, 6.75, 6.375 should be displayed.

These two buttons work out squares and square roots, for example 3.5² is found by entering 3.5 to obtain 12.25. The square root of 256 is found by entering 256 to get 16.
You will need these buttons when solving problems using Pythagoras's theorem. If the two shorter sides of a right-angled triangle are 4 cm and 7 cm, then the longest side (the hypotenuse) can be found by entering 47 to get 8.062257748

These three buttons are use to find the sine, cosine and tangent of an angle. To find cos (30°) enter 30 and the calculator will display 0.866025403.
To find the angle whose tangent is 1.3, you use the tan^-1 function obtained by pressing SHIFT (or 2nd on some calculators) then .
So SHIFT1.3 will display 52.43140798.
Remember that your calculator must be set to DEG (not RAD or GRA) for this to work correctly.