Question

What is the value of cos 45° + sin 45°?

(a) 1

(b) \( \frac {1}{4}\)

(c) \( \frac {3}{4}\)

(d) √2

The question was posed to me in unit test.

I'm obligated to ask this question of Trigonometric Ratios of  Specific Angles topic in division Trigonometry of Mathematics – Class 10

Answer 1

The correct option is (d) √2

Best explanation: cos 45° + sin 45° = \( \frac {1}{\sqrt 2} + \frac {1}{\sqrt 2}\)

= 2 × \( \frac {1}{\sqrt 2}\)  ( Since, 2 = √2 × √2 )

= √2