Question

sin45°cos45°-sin30°=
A. 0
B. 1
C. 6
D. -1

Answer 1

Answer:

Correct option (a)

$\frac{1}{ \sqrt{2} } \times \frac{1}{ \sqrt{2} } - \frac{1}{2} \\ = \frac{1}{2} - \frac{1}{2} \\ = 0$

Answer 2

Answer :

A. 0

Solution :

sin 45° cos 45° - sin 30°

(1/√2)(1/√2) - 1/2

1/(√2)² - 1/2

1/2 - 1/2

0

Note :

• sin 45° = 1/√2

• cos 45° = 1/√2

• sin 30° = 1/2