2 * tan(x)^2 - 1 = 0, solve for x between 0->2pi2 * tan(x)^2 - 1 = 0 2 * tan(x)^2 = 1 tan(x)^2 = 1/2 tan(x) = +/- *sqrt(2) / 2 Lost from here!

2tan^2 x -1 = 0

==>
2tan^2 x = 1

==> tan^2 x =
1/2

Now we know that tanx =
sinx/cosx

==> tan^2 x = sin^2 x/ cos^2
x

==> (sin^2 x) / (cos^2 x) =
1/2

Now we know that cos^2 x = 1- sin^2
x

=> sin^2 x / (1-sin^2 x) =
1/2

==> 2sin^2 x = 1- sin^2
x

==> 3sin^2 x =
1

==> sin^2 x =
1/3

==> sinx = +-sqrt(1/3)
=

==> sinx =+-
0.5774

==> x1 = +-35.26
degrees.