Solve for x trig identities? help!

Solve for x

sec^2πx = 4/π

I don't understand this please help thanks!

sec²(πx) = 4/π

Substitute 1/cos²(πx) for sec²(πx):

1/cos²(πx) = 4/π

Multiply both sides by cos²(πx):

1 = {4/π}{cos²(πx)}

Multiply both sides by π/4:

cos²(πx)= π/4

Take the square root of both sides:

cos(πx) = ±sqrt(π/4)

Take the inverse cosine of both sides:

πx = cos^-1(±sqrt(π/4))

x = {1/π}cos^-1(±sqrt(π/4))

This is two answers:

x = {1/π}cos^-1(sqrt(π/4))

x = {1/π}cos^-1(-sqrt(π/4))

Now you need a calculator.