Suppose a is inquadrant iv and b is in quadrant iii.
if cos(a)=(9/41) and cos(b)=-(8/17), then sin(a+b)=
compute sin (a-b)=

Part 1)

Part 2)

Step-by-step explanation:

Suppose A is in Quadrant IV and B is in Quadrant III.

If cos(A)=(9/41) and cos(B)=-(8/17)

Part 1) Find sin(A+B)

step 1

Find sin(A)

we know that

we have

substitute

square root both sides

Angle A is in Quadrant IV

so

sine(A) is negative

therefore

step 2

Find sin(B)

we know that

we have

substitute

square root both sides

Angle B is in Quadrant III

so

sine(B) is negative

therefore

step 3

Find sin(A+B)

we know that

we have

substitute

Part 2) Find sin(A-B)

we know that

we have

substitute