Question

In a $\Delta$ ABC, if the sides are a = 3, b = 5 and c = 4, then sin B/2 + cos B/2 is equal to

• A.
• B.
• C.
• D. 2

Answer 1

The correct option is A

$\because 3^2+4^2=5^2\Rightarrow a^2+c^2=b^2\therefore \Delta ABC\text{is a right angled triangle}\therefore sin\frac{B}{2}+cos\frac{B}{2}=\sqrt{2}$