Home
Class 12
MATHS
Let f (x) be a continuous function (defi...

Let `f (x)` be a continuous function (define for all x) which satisfies `f ^(3) (x)-5 f ^(2) (x)+ 10f (x) -12 ge 0, f ^(2) (x) + 3 ge 0 and f ^(2) (x) -5f(x)+ 6 le 0`
The equation of tangent that can be drawn from `(2,0)` on the curve `y = x^(2) f (sin x)` is :

A

`y=24 (x+2)`

B

` y= 12 (x+2)`

C

`y=24(x-2)`

D

`y=12 (x-2)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the equation of the tangent line to the curve \( y = x^2 f(\sin x) \) at the point where it touches the line from the point \( (2, 0) \). We also need to analyze the function \( f(x) \) based on the inequalities provided. ### Step 1: Analyze the inequalities for \( f(x) \) 1. **First Inequality**: \[ f^{(3)}(x) - 5f^{(2)}(x) + 10f(x) - 12 \geq 0 \] Let's denote \( f(x) \) as \( t \). Then we rewrite the inequality as: \[ t^3 - 5t^2 + 10t - 12 \geq 0 \] We can find the roots of the polynomial to analyze the intervals. 2. **Second Inequality**: \[ f^{(2)}(x) + 3 \geq 0 \] This implies: \[ f^{(2)}(x) \geq -3 \] 3. **Third Inequality**: \[ f^{(2)}(x) - 5f(x) + 6 \leq 0 \] Rewriting gives: \[ f^{(2)}(x) \leq 5f(x) - 6 \] ### Step 2: Solve the inequalities 1. From the first inequality, we can find the roots of \( t^3 - 5t^2 + 10t - 12 = 0 \). By testing values, we find that \( t = 3 \) is a root. We can factor the polynomial: \[ (t - 3)(t^2 - 2t + 4) \geq 0 \] The quadratic has no real roots (discriminant \( < 0 \)), so it is always positive. Thus, the inequality holds for: \[ t \geq 3 \] 2. The second inequality \( f^{(2)}(x) + 3 \geq 0 \) implies: \[ f^{(2)}(x) \geq -3 \] This does not restrict \( f(x) \) further. 3. The third inequality \( f^{(2)}(x) - 5f(x) + 6 \leq 0 \) can be analyzed similarly. The roots of \( t^2 - 5t + 6 = 0 \) are \( t = 2 \) and \( t = 3 \). Thus, we have: \[ 2 \leq f(x) \leq 3 \] ### Step 3: Determine \( f(x) \) From the inequalities, we conclude that: \[ f(x) = 3 \] is a valid solution since it satisfies all inequalities. ### Step 4: Find the tangent line to the curve \( y = x^2 f(\sin x) \) Substituting \( f(x) = 3 \): \[ y = 3x^2 \] ### Step 5: Find the derivative The derivative of \( y \) is: \[ \frac{dy}{dx} = 6x \] ### Step 6: Find the slope at \( x = 2 \) At \( x = 2 \): \[ \frac{dy}{dx} = 6 \cdot 2 = 12 \] ### Step 7: Write the equation of the tangent line Using point-slope form of the line: \[ y - y_1 = m(x - x_1) \] where \( (x_1, y_1) = (2, 0) \) and \( m = 12 \): \[ y - 0 = 12(x - 2) \] \[ y = 12x - 24 \] ### Final Answer The equation of the tangent line is: \[ \boxed{y = 12x - 24} \]
Promotional Banner

Topper's Solved these Questions

  • FUNCTION

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise MATCHING TYPE PROBLEMS|6 Videos
  • FUNCTION

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise SUBJECTIVE TYPE PROBLEMS|33 Videos
  • FUNCTION

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise ONE OR MORE THAN ONE ANSWE IS/ARE CORRECT|23 Videos
  • ELLIPSE

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise Exercise-4 : Subjective Type Problems|2 Videos
  • HYPERBOLA

    VIKAS GUPTA (BLACK BOOK) ENGLISH|Exercise Exercise-4 : Subjective Type Problems|3 Videos

Similar Questions

Explore conceptually related problems

Let f (x) be a continuous function (define for all x) which satisfies f ^(3) (x)-5 f ^(2) (x)+ 10f (x) -12 ge 0, f ^(2) (x) + 3 ge 0 and f ^(2) (x) -5f(x)+ 6 le 0 If distinct positive number b_(1), b _(2) and b _(3) ar in G.P. then f (1)+ ln b _1), f (2) + ln b _(2), f (3)+ ln b _(3) are in :

Let f (x) be a conitnuous function defined on [0,a] such that f(a-x)=f(x)"for all" x in [ 0,a] . If int_(0)^(a//2) f(x) dx=alpha, then int _(0)^(a) f(x) dx is equal to

Let f be a continuous function satisfying f '(l n x)=[1 for 0 1 and f (0) = 0 then f(x) can be defined as

Let f(x) be continuous functions f: RvecR satisfying f(0)=1a n df(2x)-f(x)=xdot Then the value of f(3) is 2 b. 3 c. 4 d. 5

Let f(x) be continuous functions f: RvecR satisfying f(0)=1a n df(2x)-f(x)=xdot Then the value of f(3) is 2 b. 3 c. 4 d. 5

A function f : R -> R^+ satisfies f(x+y)= f(x) f(y) AA x in R If f'(0)=2 then f'(x)=

Let f(x) be a continuous function defined for 0lexle3 , if f(x) takes irrational values for all x and f(1)=sqrt(2) , then evaluate f(1.5).f(2.5) .

The function f(x) satisfying the equation f^2 (x) + 4 f'(x) f(x) + (f'(x))^2 = 0

Let f(x) be a continuous function such that f(a-x)+f(x)=0 for all x in [0,a] . Then int_0^a dx/(1+e^(f(x)))= (A) a (B) a/2 (C) 1/2f(a) (D) none of these

Let f:R in R be a continuous function such that f(x) is not identically equal to zero. If int_(0)^(x) |x-2|dx,x ge 0 . Then, f'(x) is