Sin(x), Cos(x) and Tan(x) are very useful functions and can be used to solve algerbraic problems where the aim is to find the size of an angle or a size.

Sin(x) = Opposite/Hypotenuse

Cos(x) = Adjacent/Hypotenuse

Tan(x) = Opposite/Adjacent

these are the equations you must rearrange to solve the problems. for example if you're looking to find the length of hypotenuse side and have the angle, x and the length of the adjacent of side you rearrange the equation to be:

hypotenuse =adjacent/cos(x)

This can be confusing at first but can become second nature very quickly if you work through lots of problems.

A great way of remembering the equations is:
SOHCAHTOA

Factorise x^2-25

Related Maths GCSE answers

Whats the difference between the three main trigonometric functions?

Expand the brackets: (x + 5)(x - 3)?

Solve the simultaneous equations 2x + y = 7 and 3x - y = 8.

solve: x/4 + 2x/(x+2)=1