Question

cos square theta into (1 + tan square theta )is equal to 1​

Answer 1

Solution:

Here I am using A instead of theta.

LHS = cos²A (1+tan²A)

= cos²A×sec²A

[ Since ,1+tan²A = sec²A ]

= cos²A × ( 1/cos²A)

[ Since , secA = 1/cosA ]

= 1

= RHS

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