1.

In ΔABC, right angled at B, if sin A = \(\frac{1}{\sqrt2}\), then the value of \(\frac{sin A(cos C + cos A)}{cos C (sin C + sin A)}\) is:1. \(2 \sqrt{5}\)2. 13. 34. 2

Answer» Correct Answer - Option 2 : 1

Given :-

ΔABC is a right angle at B

sin A = (1/√2)

Concept :-

As sin A = (1/√2)

sin A = sin45° 

A = 45° 

Calculation :-

As B is right angle and,

⇒ ∠A = 45° 

Sum of triangle = 180° 

⇒ ∠A + ∠B + ∠C = 180° 

⇒ 45° + 90° + ∠C = 180° 

⇒ ∠C = 180° - 135° 

⇒ ∠C = 45° 

As ∠A = ∠C = 45° 

⇒ sin A = cos C = cos A = (1/√2)

ΔABC is an isosceles triangle 

Now, Put the value of all identities 

⇒ \(\frac{sin A(cos C + cos A)}{cos C (sin C + sin A)}\) = (sin A (sin A + sin A))/(sin A (sin A + sin A))

⇒ \(\frac{sin A(cos C + cos A)}{cos C (sin C + sin A)}\) = 1

∴  \(\frac{sin A(cos C + cos A)}{cos C (sin C + sin A)}\) = 1



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