Does anyone know if there is anyway to calculate the sin, cos and tan of those number on a simple calculator? My calculator can do multiplication, addition, subtraction and addition, of course, plus percentages. I can square numbers by typing in the number, then pressing 'multiply by' then 'equals.' I can cube numbers in the same way, and so on. But i need to perform trigonometric functions- so is there any way to work out (for example) sin 36.3 or inverse tan 3/4? Please help (or tell me that there is no way)! Thanks

sin x = x - x^3/3! + x^5/5! - x^7/7! + ...

This is the formula I was looking for. These four terms will give two digits of accuracy for an angle (in radians) up to pi/2

The cosine is similar but with even terms (it is, of course, an even function)

cos x = 1 - x^2/2! + x^4/4! - x^6/6! + ...

For tangent, just use the identity

tan x = (sin x)/(cos x)