Application of DerivativeHard
Question
If there are exactly two different tangents are possible to the curve f(x) = x4 + αx3 + βx which pass through origin, then -
Options
A.α > 0, β ∈ R
B.α < 0, β ∈ R
C.α ∈ R, β > 0
D.α ∈ R, β ∈ R
Solution
∴ jmop = 
⇒
= 4h3 + 3αh2 + β
⇒ h4 + αh3 + βh = 4h4 + 3αh3 + βh 3h4 + 2αh3 = 0
⇒ h3(3h + 2α) = 0 ⇒ h = 0, h = -
⇒ α ≠ 0 and β ∈ R
for two different values of h.

⇒
= 4h3 + 3αh2 + β⇒ h4 + αh3 + βh = 4h4 + 3αh3 + βh 3h4 + 2αh3 = 0
⇒ h3(3h + 2α) = 0 ⇒ h = 0, h = -

⇒ α ≠ 0 and β ∈ R
for two different values of h.
Create a free account to view solution
View Solution FreeMore Application of Derivative Questions
The number of values of c such that the straight line 3x + 4y = c touches the curve = x + y is -...If p, q, r are any real numbers, then...The function f(x) = x(x + 3)e-x/2 satisfies all the conditions of Rolle′s theorem on [-3, 0]. The value of c which...The interior angles of a convex polygon are in AP. The smallest angle is 120o & the common difference is 5o . Find the n...The tangent to the curve (x − 2)4 + ( y − 1)4 = 81 at the point (5, 1) is-...