Question

Find the value of
$sin\theta +cos\theta \text{,when}\theta ={45}^{\circ }$

• A. $\frac{1}{\sqrt{2}}$
• B. $\sqrt{2}$
• C. $\frac{1}{\sqrt{3}}$
• D. $\sqrt{3}$

Answer 1

The correct option is B $\sqrt{2}$

$\text{When}\theta ={45}^{\circ }$,
$sin\theta =\frac{1}{\sqrt{2}}andcos\theta =\frac{1}{\sqrt{2}}$

Hence,
$sin\theta +cos\theta =\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{2}}=\frac{2}{\sqrt{2}}=\sqrt{2}$