Question

simplify without using a calculator
cos^{2}30-sin^{2}30

Answer 1

So you know what cos and sin 30 are?

Answer 2

sin(30)=1/2 and \[\cos =\frac{ \sqrt{3} }{ 2 }\]

Answer 3

K, where u having the problem?

Answer 4

the ^2

Answer 5

Also note these two:\[\sin^2 (x) = (\sin x)^2 \\ \cos^2 (x) = (\cos x)^2\]

Answer 6

Multiply by itself?

Answer 7

ooooooh ok thanx

Answer 8

ur welcome

Answer 9

For example,\[\sin^2(\pi) = (\sin \pi)^2 = \cdots\]

Answer 10

You're welcome... maybe

Answer 11

thanx now i know