Question

if tan 2A = cot A then sin 3A by 2 is equal to

Answer 1

tan2A=cotA
(put cotA= tan (90-A))
tan2A=tan(90-A)
we get, 2A=90-A
3A=90
now, sin3A÷2
put value of 3A
sin 90 ÷2
we get , sin 45
we know that sin45 =1/√2
so, answer is 1/√2