Question

The curve represented by x = 3(cost + sint); y = 4(cost – sint) is  

(a) circle

(b) parabola

(c) ellipse

(d) hyperbola

Answer 1

The correct option (c) ellipse 

Explanation:

x = 3(cos t + sint)

y = 4(cos t – sint)

∴   (x/3)² + (y/4)² = (cost + sint)² + (cost – sint)²

∴   (x²/9) + (y²/16) = 2

This represents an ellipse.