Q2 of 90 Page 7

If sinA = 3/5, cosB = –12/13, where A And B Both lie in second quadrant, find the value of sin(A +B).

Given sinA = 3/5 And cosB = -12/13


A And B lie in the second quadrant.


So sine function is positive And cosine function is negative.


We know that






Now consider sin(A +B),


⇒ sin(A +B)




More from this chapter

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1

If sinA = 4/5 And cosB = 5/13, where 0 <A, B < π/2, find the values of the following:

(i) sin(A +B)


(ii) cos(A +B)


(iii) sin(A –B)


(iv) cos(A -B)

 2

If SinA = 12/13 And sinB = 4/5, where π/2<A < π And 0 <B < π/2, find the following:

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

 3

If cosA = – 24/25 And cosB = 3/5, where π <A < 3π/2 And 3π/2 <B < 2π, find the following:

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

 4

If tanA = 3/4, cosB = 9/41, where π<A < 3π/2 And 0 <B < π/2, find tan(A +B).