Question

If cota=7/8 evaluate (1+sina)(1-sina)/(1+cosa)(1-sina)
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Answer 1

Answer:

Given:

=  

We have to find, the value of  is:

Solution:

∴  

Using the algebraic identity:

(a + b)(a - b) =  

Using the trigonometric identity:

+  = 1

⇒  = 1 -  and  = 1 -  

Using the trigonometric identity:

=  

=  

Put  = , we get

=  

=  

∴  =  

Thus, the value of  is "equal to ".

Explanation: