Question

Help I have 10 mins.

Answer 1

`√(0.5)`

Explanation:

cosx=adj/hyp

adj=
`√(2)`/2

hyp= r

cos(45)= (
`√(2)`/2)/r

`√(2)`/2 = (
`√(2)`/2)/r

multiply both sides by r

(
`√(2)`/2)r =
`√(2)`/2

divide both sides by
`√(2)`/2

r = 1

pythagorean theorem:
`a^(2)` +
`b^(2)` =
`c^(2)`

a =
`√(2)`/2

b = y

c = r = 1

`(√(2)/2)^(2)` +
`y^(2)` =
`1^(2)`

`(√(2)/2)^(2)` = 2/4 = 0.5

0.5 +
`y^(2)` = 1

subtract 0.5 from 1

`y^(2)` = 0.5

`\sqrt{y^(2)}` =
`√(0.5)`

y =
`√(0.5)`