Question

please help me to do this sum

Answer 1

HEY FRIEND

HERE IS YOUR ANSWER

=sec²40-cot²50

[USING sec@=cosec(90-@)]

=cosec²(90-40)-cot²50

=cosec²50-cot²50

[Using cosec²@-cot²@=1]

=1

HOPE THIS HELPS YOU ☺

Answer 2

sec²40-cot²50

[USING sec@=cosec(90-@)]

=cosec²(90-40)-cot²50

=cosec²50-cot²50

[Using cosec²@-cot²@=1]

=1