Answer:
see explanation
Step-by-step explanation:
Using the identities
cotA = [tex]\frac{1}{tanA}[/tex]
cot²A = cosec²A - 1
tan²A = sec²A - 1
Consider the left side
(cotA + tanA)² ← expand using FOIL
= cot²A + 2cotAtanA + tan²A
= cosec²A - 1 + 2 .[tex]\frac{1}{tanA}[/tex] . tanA + sec²A - 1
= cosec²A - 1 + 2 + sec²A - 1
= sec²A + cosec²A - 2 + 2
= sec²A + cosec²A
= right side, thus proven
