Question

evaluate ( tan 20/ cosec 70)^2 + ( cot 20/ sec 70)^2 + 2tan15 tan45 tan 75

Answer 1

hello..
(tan20/cosec70)2+(cot20/sec70)^2+2tan15tan45tan75
={tan(90-20)/cosec70}^2+{cot90-20)/sec70}^2+2(tan90-15)tan45 tan 75
=(cot70/cosec70)^2 + (tan70/sec70) ^2+ 2(cot75 tan 45 tan75 )
=(cos 70/sin70/1/sin70)^2 +(sin70/cos70/1/cos70) ^2+2(1×1)
=(cos70+sin70)^2 +2
=1+2
=3...
i hope it help you.....
please mark it as a brainieist answer.............

Answer 2

Answer:

Step-by-step explanation:

(tan20/cosec70)2+(cot20/sec70)^2+2tan15tan45tan75

={tan(90-20)/cosec70}^2+{cot90-20)/sec70}^2+2(tan90-15)tan45 tan 75

=(cot70/cosec70)^2 + (tan70/sec70) ^2+ 2(cot75 tan 45 tan75 )

=(cos 70/sin70/1/sin70)^2 +(sin70/cos70/1/cos70) ^2+2(1×1)

=(cos70+sin70)^2 +2

=1+2

=3