Question

What is sin 45°? O A. 1/2 12 1 OB. NI O C. 1 O D. O E. 1 3 O F. 13 ap.ex​

Answer 1

1/√2

Step-by-step explanation:

Imagine a right-angled triangle, for e.g. Triangle ABC,

Where

B = 90°

Remember your Toa Cah Soh.

sin 45° = opposite / hypotenuse

If theta = 45°

Angles A and C = 45° (Sum of angles in a triangle equal = 180°)

Since theta are the same, we can also deduce that the length AB and BC are the same.

Take for example AB = BC = 1 = opposite

By the Pythagorean theorem,

AB² + BC² = AC²

1² + 1² = AC²

2 = AC²

AC = √2 = hypotenuse

Therefore:

sin 45° = opposite / hypotenuse

sin 45° = 1/√2