Question

Solve 4 sec sqrd x = 8

Answer 1

4 sec²(x) = 8

Divide each side by 4: sec²(x) = 2

Take the square root of each side: sec(x) = + or - √2

We know that sec(x) = 1/cos(x)

So the equation becomes 1/cos(x) = + or - √2

Divide '1' by each side: cos(x) = + or - (1/2) √2

x = 45°, 135°, 225°, 315°