In: Advanced Math
solev tan^2 x =1 where x is more than or equal to 0 but x is less than or equal to pi
tan2(x) = 1 , 0 ≤ x ≤ Π
tan2(x) = 1 ==> (tan(x))2 = 1
√(tan(x))2 = √1 ==> tan(x) = ± 1
Note the following: tan(x) = sin(x)/cos(x)
So, tan(x) = ± 1 ==> sin(x)/cos(x) = ± 1
Multiply both sides of the equation by cos(x):
(cos(x))·(sin(x)/cos(x)) = (cos(x))·(± 1)
sin(x) = ± cos(x)
Looking at the top half of a unit circle (where x is between 0 and Π)...
...find the coordinates where sin(x) = cos(x) and sin(x) = -cos(x)
You will see that the coordinates that match are (√2/2, √2/2), which is located at x = ∏/4, and (-√2/2, √2/2), which is located at x = 3Π/4.
Thus, x = Π/4 and x = 3Π/4
pi/4 amd 3pi/4