For non zero real numbers l,m,n and a, let f(x) =lx3 +mx + n, and f(a) = f(4a) Then - Maths - Matrices

Question

For non zero real numbers l,m,n and a, let f(x) =lx3 +mx
+ n, and f(a) = f(4a) Then the value x belonging to [a,4a], at
which the tangent to the curve y=f(x) is parallel to x axis is : i)
a root 5 , ii) 3a ,iii) a root 7 ,iv) 2a No links

Arnab Gupta · Accepted Answer

Dear student,
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For non zero real numbers l,m,n and a, let f(x) =lx3 +mx + n, and f(a) = f(4a). Then the value x belonging to [a,4a], at which the tangent to the curve y=f(x) is parallel to x axis is : i) a root 5 , ii) 3a ,iii) a root 7 ,iv) 2a. No links

For non zero real numbers l,m,n and a, let f(x) =lx³ +mx + n, and f(a) = f(4a). Then the value x belonging to [a,4a], at which the tangent to the curve y=f(x) is parallel to x axis is : i) a root 5 , ii) 3a ,iii) a root 7 ,iv) 2a. No links