We have to evaluate sin (π/2)
Solution
sin(π/2) = sin 90
From the basic knowledge of trigonometry, we conclude that for the given right-angled triangle, the base measuring ‘x’ units and the perpendicular measuring ‘y’ units.
We know that,
For any right-angled triangle measuring with any of the angles, sine functions equal to the ratio of the length of the opposite side to the length of the hypotenuse side.
sinθ = y/1
Start measuring the angles from the first quadrant and end up with 90° when it reaches the positive y-axis. Now the value of y becomes 1 since it touches the circumference of the circle. Therefore the value of y becomes 1.
sinθ = y/1 = 1/1
Therefore, sin 90 degree equals to the fractional value of 1/ 1.
Sin 90° = 1
or sin (sin(π/2) = sin 90° = 1
