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Write the expression in terms of sine ans cosine, and simplify so that no questi

ID: 3400751 • Letter: W

Question

Write the expression in terms of sine ans cosine, and simplify so that no questions appear in the final expression. sin^2x + sin^21 x cot^2 x A) cot^2 x - 1 B) 1 C) sin^2 x + 1 D) cot^2 x + 1 Find the exact value of the expression using the provided information. Find tan(s - t) given that sin s = -3 squareroot 13/13, with s in quadrant IV, and sin t = - squareroot 10/10, with t in quadrant IV. A) -7/9 C) 11/3 C) -11/3 D) -11/9 Perform the indicated operations and simplify the result so there are no quotients. tan^2 theta - 3 sin theta tan theta sec theta A) 1 + cot theta B) sec theta csc theta C) sin theta tan theta D) -2 tan^2 theta Solve the equation for x, where x is restricted to the given interval. y = 8 cos 3x, for x in [0, pi/3]] A) x = 1/3 arccos y/8 B) x = 1/8 arccos y/3 C) x = 8 arccos y/3 D) x = 3 arccos y/8 Use a calculator to give the value to the nearest degree. theta = sin^-1(0.8830) A) 57 degree B)62 degree C) 60 degree D) 118 degree Write the product as a sum or difference of trigonometric functions. 2 sin 2x sin 12x A) cos 14x + cos 10x B) 1/2 (cos 14x + cos 10x) C) sin 14x + sin 10x D) cos 10x - cos 14x Find the exact value of the real number y. y = cos^-1(squareroot 2/2) A) pi/4 B) 11 pi/6 C) 7 pi/4 D) pi/6 Use identities to find the exact value. cos 165 degree A) - squareroot 6 - squareroot 2/4 B) squareroot 2 - squareroot 6/4 C) squareroot 6 - squareroot 2/4 D) squareroot 6 + squareroot 2/4

Explanation / Answer

8. sin2x + sin2xcot2x

sin2x(1+cot2x)

and 1 + cot2x=csc2x

So we get

sin2x*csc2x= 1

9.sin s=-3sqrt13/13 =-3/sqrt13

cos s= 2/sqrt13

tan s= -3/2

sin t=-sqrt10/10=-1/sqrt10

cos t= 3/sqrt10

tan t= -1/3

tan(s-t)=(tans - tant)/(1+tan s tan t)= (-3/2 +1/3)/(1+(-3/2)(-1/3))

                                                  = (-7/6)/(9/6) = -7/9

10. tan2theta - 3sin theta tan theta sec theta

tan theta(tan theta - 3 sin theta sec theta)

And sin theta sec theta=tan theta

tan theta(tan theta-3tan theta)= tan theta(-2 tan theta)=-2tan2theta