Question

(11) COS 3
COS 32
sin 38 sin 52 = 0
3. If tan 2A = cot(A - 18°), where 2A is an acute angle find the
4. Iftan A = cot B, prove that A + B = 90°
5. If sec 4A = cosec (A - 20°), where 4A is an acute angle.fi
lanes​

Answer 1

Answer:

Step-by-step explanation:

question 3=

=tanA=cotB

=sinA/cosA=cosB/sinB

=cross multiply it will give you

=cos(A+B)=0

as cos90=0

=then A+B=90