Question

Let l be a line which is normal to the curve y = 2x² + x + 2 at a point P on the curve. If the point Q(6, 4) lies on the line l and O is origin, then the area of the triangle OPQ is equal to _____.

Answer 1

Correct answer is 13

y = 2x² + x + 2

dy/dx = 4x + 1

Let P be (h, k), then normal at P is

Now area of ΔOPQ will be

= 

Answer 2

Answer: 13

\(\frac{y_1-4}{x_1-6}=-\frac{1}{{4x_1}+4}\)