Drag point B to change the size of the triangle. This will not change the size of theta. Drag point C to change the shape of the triangle. This will change the size of theta. Pay attention to the values of sin, cos and tan ratios.
When theta is constant, will the values of sin, cos and tan ratios change? What happen to the values of sin, cos and tan ratios when theta increases? What happen to the values of sin, cos and tan ratios when theta decreases?