Q11 of 149 Page 16

The equation of tangent at those points where the curve y = x2 – 3x + 2 meets x-axis are

Given that the curve y = x2 – 3x + 2



The tangent passes through point (x, 0)


⇒ 0 = x2 – 3x + 2


⇒ (x-2)(x-1)=0


⇒ x = 1 or 2


Equation of the tangent:


(y-y1)=Slope of tangent×(x-x1)


Case: 1


When x = 2


Slope of tangent = 1


Equation of tangent:


y = 1× (x – 2)


⇒ x – y – 2 = 0


Case: 2


When x = 1


Slope of tangent = -1


Equation of tangent:


y = -1× (x – 1)


⇒ x + y – 1 = 0


Hence, option B is correct.

More from this chapter

All 149 →
9

The angle between the curves y2 = x and x2 = y at (1, 1) is

 10

The equation of the normal to the curve 3x2 – y2 = 8 which is parallel to x + 3y = k is

 12

The slope of the tangent to the curve x = t2 + 3t – 8, y = 2t2 – 2t – 5 at point (2, –1) is

 13

At what points the slope of the tangent to the curve x2 + y2 – 2x – 3 = 0 is zero.