MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping
Menu
nitin singh Grade: 12
        

a) Find p so that the curve y = x 3 + 2 x 2 + p x + 3 has one horizontal tangent line only.

b) Find the value of x where this tangent line occurs.

7 years ago

Answers : (1)

SAGAR SINGH - IIT DELHI
879 Points
										

Dear nitin,




  • a) The horizontal tangent line has a slope equal to zero. We first need to find the first derivative of y and equate to 0.

    y ' = 3 x 2 + 4 x + p = 0


  • For the above quadratic function to have one solution only, it needs to have its discriminant D equal to zero.

    D = 16 - 12 p = 0


  • Solve the above for p to find

    p = 4 / 3


  • b) To find the value of x where the horizontal tangent line occurs, we need to solve the above quadratic equation 3 x 2 + 4 x + p = 0 for x. It had the discriminant equal to zero, hence

    x = - 4 / 6 = - 2 / 3






We are all IITians and here to help you in your IIT JEE preparation.

All the best.


 If you like this answer please approve it....


win exciting gifts by answering the questions on Discussion Forum


 





Sagar Singh


B.Tech IIT Delhi







7 years ago
Think You Can Provide A Better Answer ?
Answer & Earn Cool Goodies
  • Complete JEE Main/Advanced Course and Test Series
  • OFFERED PRICE: Rs. 15,900
  • View Details

Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers
To Win!!! Click Here for details