Question

Use the sum/difference identities to solve using the given information.
Given sinx=rad 2/5, where pi/2 10 years ago

Answer 1

@tkhunny

Answer 2

Have you considered stating the identity?

\(\sin(x+y) = \sin(x)\cos(y)+\cos(x)\sin(y)\)

Answer 3

yes i know it

Answer 4

Use the Pythagorean Theorem and the Quadrant Hints to find the cosine of x.

Answer 5

ok

Answer 6

What do you get?

Answer 7

1 sec

Answer 8

Do the same for the y in Quadrant III

Answer 9

Gaaa!!! You'll never make the State Finals like that!

Answer 10

? for cos x is it in quadrant 1?

Answer 11

Why would it be? We are told explicitly that x in in II.

Answer 12

do i use sin x?

Answer 13

i got rad 23 for

Answer 14

We're trying that again.

Answer 15

Very good. What is the cosine of that angle?

Answer 16

rad 23 /5