Question

1. What is the value of cos 90° and cos 0°?
2. Simplify : tan 45º . sin 60° . cos.45°
8. Find the value of cos? 45° + sin 0°
4. Simplify : sina 30° + sin2 45° + sina 60°​

Answer 1

Answer:

1) cos 90° = 0

cos 0° = 1

2) tan 45º . sin 60° . cos.45°

=

$1 \times (\sqrt{3 } \div 2) \times (1 \div \sqrt{2)}$

$\sqrt{3} \div (2 \times \sqrt{2} )$

3) cos45° + sin 0°

=

$\frac{1}{\sqrt{2} } + 0$

$\frac{1}{ \sqrt{2} }$

4)sin 30° + sin 45° + sin 60°

$\frac{1}{2} + \frac{1}{ \sqrt{2} } + \frac{ \sqrt{3} }{2}$

$\frac{1 + \sqrt{2} + \sqrt{3} }{2}$