Originally Posted by

**Blahdkm** I'm terrible at trig, mind if I get some explanation on the following questions?

1) What is the exact value of sin2(pi/6) - 2sin(pi/6)cos(pi/6) + cos2(-pi/6)

a)2 - SqRt(3)

b)(2- SqRt(3))/2

c)(2+SqRt(3))/2

d)2+SqRt(3)

2) If cos(x)= -sin(x), then sin2(x) is

a)1/4

b)1/2

c)SqRt(2)/2

d)-SqRt(2)/2

3)For the equation 4cos(x) - SqRt(12) = 0, where 0<x<(or equal to)2pi, determine the measure of x.

a)pi/3, 5pi/3

b)2pi/3, 4pi/3

c)5pi/6 , 7pi/6

d)pi/6 , 11pi/6

4)If cos2(x) - 6sin(2x)=0, then one value of x is

a)0 Degrees

b)90 Degrees

c)180 Degrees

d)255 Degrees

5) For the graph of y=2sin(3x), which of the following is not an x-intercept?

a)60 Degrees

b)90 Degrees

c)240 Degrees

d)2pi Rad

6)What is another form of Sin(A+B)sin(A-B)/cos2(A)cos2(B)

a)cos2(A) - cos2(B)

b)Tan2(A) + Tan2(B)

c)Tan2(A) - Tan2(B)

d)sin2(A) - sin2(B)