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Let `f(x)` be a real valued continuous function on `R` defined as `f(x)=x^2e^(-|x|)` The value of `k` for which the curve `y=k x^2(k >0)` intersect the curve `y=e^(|x|)` at exactly two points, is `e^2` (b) `(e^2)/2` (c) `(e^2)/4\ ` (d) `(e^2)/8`

A

`(e^(2))/4ltkltoo`

B

`(e^(2))/2`

C

`(0ltklt=4)/(e^(2))`

D

`(e^(2))/4`

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The correct Answer is:
To solve the problem, we need to find the value of \( k \) such that the curves \( y = kx^2 \) and \( y = e^{|x|} \) intersect at exactly two points. ### Step 1: Set the equations equal to each other We start by setting the two equations equal to each other: \[ kx^2 = e^{|x|} \] ### Step 2: Analyze the equations Since \( e^{|x|} \) is an even function, we can analyze the intersections for \( x \geq 0 \) and \( x < 0 \) separately. For \( x \geq 0 \), we have: \[ kx^2 = e^x \] For \( x < 0 \), we have: \[ kx^2 = e^{-x} \] ### Step 3: Find the intersection points for \( x \geq 0 \) We will focus on the case \( x \geq 0 \) first: \[ kx^2 - e^x = 0 \] This is a quadratic equation in terms of \( x \). ### Step 4: Find the derivative To determine the number of intersection points, we can analyze the function: \[ g(x) = kx^2 - e^x \] We find the derivative: \[ g'(x) = 2kx - e^x \] ### Step 5: Find critical points Set the derivative to zero to find the critical points: \[ 2kx = e^x \] This equation will help us determine the behavior of \( g(x) \). ### Step 6: Analyze the second derivative To find the nature of the critical points, we can analyze the second derivative: \[ g''(x) = 2k - e^x \] This will help us determine if we have a maximum or minimum. ### Step 7: Find the conditions for two intersections For the curves to intersect at exactly two points, the quadratic \( kx^2 \) must be tangent to \( e^{|x|} \) at one point and intersect at another point. This means that the discriminant of the quadratic equation must be zero for one intersection and positive for another. ### Step 8: Set up the discriminant condition The discriminant \( D \) of the equation \( kx^2 - e^x = 0 \) must be zero: \[ D = b^2 - 4ac = 0 \] This leads to the condition on \( k \). ### Step 9: Solve for \( k \) We can find the specific value of \( k \) by substituting \( x = 2 \) into the equation: \[ k(2^2) = e^2 \implies 4k = e^2 \implies k = \frac{e^2}{4} \] ### Final Answer Thus, the value of \( k \) for which the curves intersect at exactly two points is: \[ \boxed{\frac{e^2}{4}} \]

To solve the problem, we need to find the value of \( k \) such that the curves \( y = kx^2 \) and \( y = e^{|x|} \) intersect at exactly two points. ### Step 1: Set the equations equal to each other We start by setting the two equations equal to each other: \[ kx^2 = e^{|x|} \] ...
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