Question

What is cos 45º?...........

Answer 1

`(1)/(√(2) )`

Explanation:

Cosine (cos) is adjacent by hypotenuse.
`(adjacent)/(hypotenuse)`

In any of the 45° angles, 1 is adjacent and √2 is the hypotenuse.

So arrange them to get
`(1)/(√(2) )`