Question

sinA. (cotA+3) (3cotA + 1) = 3 cosecA + 10 cosA​

Answer 1

Step-by-step explanation:

=[(3cot^2A+cotA+9cotA+3)][sin]

=[(3cot^2A+10cotA+3)][sin]

=[(3cos^2/sin^2)+(10cos/sin)+3][sin]

=[(3cos^2+10sin.cos+3sin^2)/sin^2][sin]

=[(3cos^2+3sin^2+10sin.cos)/sin^2][sin]

=[(3+10sin.cos)/sin^2][sin]

=[(3cosec^2+10cosec.cos)][sin]

=[(3sin+10cos)]

Hence proved!