Q10 of 90 Page 7

Prove that:

LHS




We know that sin(A ±B) = sinA cosB ± cosA sinB


= RHS


Hence, proved.


More from this chapter

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8

If cosA = –12/13 and cotB = 24/7, where A lies in the second quadrant and B in the third quadrant, find the values of the following:

(i) sin(A +B) (ii) cos(A +B) (iii) tan(A +B)

 9

Prove that: cos 7π/12 + cos π/12 = sin 5π/12 – sin π/12

 11

Prove that:

(i) (ii)


(ii)

12

Prove that: