# math

posted by
**chyrl** on
.

Can anyone help w/ these.

1) Solve the equation in the internal [0deg, 360deg].

a) sin 2x = -sin x

b) sin 2T = -1/2 (where T is angle)

c) 4 sin^2T = 3

2) Evaluate the expression.

sin(arctan 2)

3) Rewrite the following w/o using trigonometric or inverse tirgonometric functions.

cos(arcsin u)

In a use the double angle formula: Sin2X= 2sinXcosX

When you divide through by sinX, be certain to remember to test to see if X=0 is a solution also.

In b, solve for 2T (then divide it by two).

in C, take the square root of each side, solve for sinT, and then T.

in 2, remember solve for arcTan2, then what is the sine of that?

In 3, remember that if sine = u, then cos of the complementary angle is u.