Question

If A = 60 and B = 30, show that sin( A - B ) / sin ( A + B) = cotB - cotA

Answer 1

Answer:

***sin(A-B)/sin(A+B)

sin(60-30)/ sin(60+30)

sin30°/sin90°

(1/2)/1

1/2

***cot B-cot A

cot30°-cot60°

√3-1/√3

(3-1)/√3

2/√3

therefore,

sin(A-B)/sin(A+B) is not equal to cot B-cotA