wiz-icon
MyQuestionIcon
MyQuestionIcon
2
You visited us 2 times! Enjoying our articles? Unlock Full Access!
Question

The triangle formed by the tangent to the curve f(x)=x2+bx-bat the point (1,1) and the coordinate axes lie in the first quadrant. If its area is 2, then the value of b is


A

-1

No worries! We‘ve got your back. Try BYJU‘S free classes today!
B

3

No worries! We‘ve got your back. Try BYJU‘S free classes today!
C

-3

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D

1

No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C

-3


Explanation for correct option :

Let y=fx

Given f(x)=x2+bx-b

m=dydxm=ddxx2+bx-bm=2x+b

The equation of the tangent at (1,1)

y-y1=mx-x1y-1=b+2x-1y-1=bx-b+2x-2y-xb+2+b+1=0

We know that Area of triangle =12×base×height

2=12×b+1b+2×-b+14b+8=-b2-2b-1b2+6b+9=0b+32=0b=-3

Hence Option(C) is the answer.


flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon