Question

86. If

tan A-tan B =x and cot B-cotA=y,
then what is cot(A - B) equal to?

Answer 1

Answer:

x+y.

Step-by-step explanation:

We know,cot(A-B)=(cotAcotB+1)/cotB-cotA

here,tanA-tanB=x

=>(cotB-cotA)/cotAcotB=x

=>cotAcotB=x/y

Now,cot(A-B)=(x/y+1)/y={(x+y)/y}/y=x+y.

I think it is correct. I am not sure.