Question 610166
sin(120)
Since 120 is in the 2nd quadrant, the reference angle is 180 - 120 or 60 degrees.
sin(60) = {{{sqrt(3)/2}}}
Since sin is positive in the 2nd quadrant sin(120) = {{{sqrt(3)/2}}}<br>
cos(300)
Since 300 is in the 4th quadrant, the reference angle is 360-300 = 60 degrees.
cos(60) = 1/2
Since cos is positive in the 4th quadrant, cos(300) = 1/2 and {{{cos^2(300) = (1/2)^2 = 1/4}}}<br>
tan(135)
Since 135 is in the 2nd quadrant, the reference angle is 180 - 135 = 45 degrees.
tan(45) = 1
Since tan is negative in the 2nd quadrant, tan(135) = -1 and {{{tan^2(135) = (-1)^2 = 1}}}<br>
Since I cannot tell if you problem is
{{{sin(120)+cos^2(300)/tan^2(135)}}}
or
{{{(sin(120)+cos^2(300))/tan^2(135)}}}
I'll leave it up to you to substitute in the values for sin(120), {{{cos^2(300)}}} and {{{tan^2(135)}}} and simplify.