anybody want to explain the importance of sin, cosine and tangent?

Sine, cosine, tangent are use to find the sides of a right triangle and its angles. Sin theta = opposite/hyponuse Cos theta = adjacent/hyponuse tan theta = opposite/adjacent Opposite and adjacent are the side according to the angle from that triangle. If you have the given two sides you can find the theta or if you have theta and a side you can find the other sides.