Math help please?

Question

if you know that sin x = ±1/√2 how do you find out what x is?

Answer 1

You memorize cosine and sine for key values like 30, 45, 60, and 90 degrees, know what those angles are in terms of radians, and keep a mental picture of the coordinate axes in your head.

Then you would know that sin(45) = sqrt(2)/2. You would also know that sin(90+45) = sqrt(2)/2. And so forth.

[I'm assuming you know that 1/sqrt(2) = sqrt(2)/2.]

Answer 2

Use a calculator.

x = sin^-1(±1/√2) = ± 45

Answer 3

If you draw a right angled triangle with two 45 degree angles and two sides of one unit length. Then the hypotenuse will be sqrt(1^2+1^2) ie sqrt2. Since sin(theta) is equal to opposite over hypotenuse, then sin(theta) = 1/sqrt2. So theta equals 45 degrees or Pi/4rads.

Answer 4

sorry no can do