MENU
Question -

Find the equation of the normals to thecurve y = x3 + 2+6 which are parallel to the line x + 14y + 4 = 0.



Answer -

The equation of the given curve is y = x3 +2x + 6.

The slope of the tangent to the given curveat any point (xy) is given by,

Slope of the normal to the given curve at any point (xy)=

The equation of the given line is x +14y + 4 = 0.

x +14y + 4 = 0  (which is of the form y = mx + c)

Slope of the given line = 

If the normal is parallel to the line, then we must havethe slope of the normal being equal to the slope of the line.

When x = 2, y =8 + 4 + 6 = 18.

When x = −2, y =− 8 − 4 + 6 = −6.

Therefore, there are two normals to the given curvewith slopeand passing through the points (2, 18)

 and (−2, −6).

Thus, the equation of the normal through (2, 18) isgiven by,

And, the equation of the normal through (−2, −6) is givenby,

Hence, the equations of thenormals to the given curve (which are parallel to the given line) are

Comment(S)

Show all Coment

Leave a Comment

Free - Previous Years Question Papers
Any questions? Ask us!
×