Cot x = cos x / sin x
cot π/4 = cot 45° = cos 45° / sin 45°
We know that sin 45° and sin 45° have the same value:
cos 45° = sin 45° = √2 / 2;
cos 45° / sin 45° = √2/2 : √2/2 = 1
Answer:
cot π/4 = 1
To find the number of wrappers he needs, divide 360 by 40. This is your answer. 360/40 = 9