Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Advanced 2009Paper 2
Exam
JEE Advanced
Year
2009
Paper
Paper 2
Subject
Mathematics
Chapter
Application of Derivatives

JEE Advanced 2009 · Paper 2 · Mathematics · Application of Derivatives

Let p(x) be a polynomial of degree 4 having extremum at x=1,2 and _...

Let p(x)p(x) be a polynomial of degree 4 having extremum at x=1,2x=1,2 and lim⁡x→0[1+p(x)x2]=2\lim _{x \rightarrow 0}\left[1+\frac{p(x)}{x^2}\right]=2. Then, the value of p(2)p(2) is

Correct answer

0

Step-by-step solution

Let p(x)=ax4+bx3+cx2+dx+ep(x)=a x^4+b x^3+c x^2+d x+e \Rightarrow \quad p^{\prime}(x)=4 a x^3+3 b x^2+2 c x+d \therefore \quad p^{\prime}(1)=4 a+3 b+2 c+d=0 and $p^{\prime}(2)=32 a+12 b+4 c+d=0$ Since, $\lim _{x \rightarrow 0}\left(1+\frac{p(x)}{x^2}\right)=2 \quad$ [given] $ \lim _{x \rightarrow 0}$ $\frac{a x^4+b x^3+(c+1) x^2+d x+e}{x^2}=$2 $\begin{array}{rlrl} \Rightarrow & & x+1=2, d & =0, e=0 \\ \Rightarrow & c & =1 \end{array}$ From Eqs. (i) and (ii) $\begin{array}{rlrl} & & 4 a+3 b=-2 & \text{ and } 32 a+12 b=-4 \\ \Rightarrow & & a=\frac{1}{4} \text{ and } b=-1 \\ \therefore & & p(x)=\frac{x^4}{4}-x^3+x^2 \\ \Rightarrow & & p(2)=\frac{16}{4}-8+4 \end{array}$
Practice Application of Derivatives on Quantrex Academy →

More from Application of Derivatives

Consider the function f: (0, ∞) arrow (-∞, ∞) given by f(x) = x \, _e(x) - x + 1 . Then… JEE Advanced 2026Let P be the point on the parabola y = x^2 such that the slope of the tangent to the… JEE Advanced 2026Let f: ℝ arrow ℝ be a differentiable function such that f((x+y)/(3)) = (f(x) + f(y))/(3)… JEE Main 2026_ 0 ≤ x ≤ π (16 ((x)/(2)) ^3((x)/(2))) is equal to: JEE Main 2026Let f(x) be a polynomial of degree 5 , and have extrema at x = 1 and x = -1 . If _ x → 0… JEE Main 2026The number of critical points of the function f(x) = cases |( x)/(x)|, & x ≠ 0 1, & x = 0… JEE Main 2026Let f be a differentiable function satisfying f(x)=1-2 x+∫_ 0 ^ x e^ (x-t) f(t) dt, x ∈ R… JEE Main 2026Consider the following three statements for the function f:(0, ∞) arrow ℝ defined by… JEE Main 2026Let (2 α, α) be the largest interval in which the function f(t)= |t+1| t^ 2 , t 2 , is… JEE Main 2026Let f(x)=x^ 2025 -x^ 2000 , x ∈[0,1] and the minimum value of the function f(x) in the… JEE Main 2026Let f: ℝ → ℝ be a twice differentiable function such that f''(x) > 0 for all x ∈ ℝ and… JEE Main 2026Let f: R arrow R be a twice differentiable function such that the quadratic equation f(x)… JEE Main 2026Let ℝ denote the set of all real numbers. Define the function f: R arrow R by f(x)=\… JEE Advanced 2025Let ℝ denote the set of all real numbers. For a real number x , let [x] denote the… JEE Advanced 2025Let ℝ denote the set of all real numbers. Let f: ℝ arrow ℝ be defined by f(x)= cases (6… JEE Advanced 2025Let the function f(x)=(x)/(3)+(3)/(x)+3, x ≠ 0 be strictly increasing in (-∞, α_1) U(α_2… JEE Main 2025 Full Application of Derivatives list Application of Derivatives JEE Maths PYQsJEE Mathematics PYQs All JEE Advanced PYQs