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The value of (dy)/(dx) at x=(pi)/(2), wh...

The value of `(dy)/(dx)` at `x=(pi)/(2)`, where y is given by
`y=x^(sinx)+sqrt(x)`, is

A

`1+(1)/(sqrt(2pi))`

B

1

C

`(1)/(2pi))`

D

`1-(1)/(sqrt(2pi))`

Text Solution

AI Generated Solution

The correct Answer is:
To find the value of \( \frac{dy}{dx} \) at \( x = \frac{\pi}{2} \) for the function \( y = x^{\sin x} + \sqrt{x} \), we will differentiate the function and evaluate it at the specified point. ### Step-by-Step Solution: 1. **Differentiate the function**: We have: \[ y = x^{\sin x} + \sqrt{x} \] We will differentiate this function with respect to \( x \). For the first term \( x^{\sin x} \), we can use logarithmic differentiation: \[ \ln y_1 = \sin x \ln x \] Differentiating both sides: \[ \frac{1}{y_1} \frac{dy_1}{dx} = \cos x \ln x + \sin x \cdot \frac{1}{x} \] Thus, we have: \[ \frac{dy_1}{dx} = y_1 \left( \cos x \ln x + \frac{\sin x}{x} \right) \] Substituting back for \( y_1 \): \[ \frac{dy_1}{dx} = x^{\sin x} \left( \cos x \ln x + \frac{\sin x}{x} \right) \] For the second term \( \sqrt{x} \): \[ \frac{dy_2}{dx} = \frac{1}{2\sqrt{x}} \] Therefore, the total derivative \( \frac{dy}{dx} \) is: \[ \frac{dy}{dx} = \frac{dy_1}{dx} + \frac{dy_2}{dx} \] Substituting the expressions we found: \[ \frac{dy}{dx} = x^{\sin x} \left( \cos x \ln x + \frac{\sin x}{x} \right) + \frac{1}{2\sqrt{x}} \] 2. **Evaluate at \( x = \frac{\pi}{2} \)**: Now we substitute \( x = \frac{\pi}{2} \): \[ y_1 = \left( \frac{\pi}{2} \right)^{\sin\left(\frac{\pi}{2}\right)} = \left( \frac{\pi}{2} \right)^{1} = \frac{\pi}{2} \] \[ \cos\left(\frac{\pi}{2}\right) = 0 \quad \text{and} \quad \sin\left(\frac{\pi}{2}\right) = 1 \] Thus, \[ \frac{dy_1}{dx} = \frac{\pi}{2} \left( 0 \cdot \ln\left(\frac{\pi}{2}\right) + \frac{1}{\frac{\pi}{2}} \right) = \frac{\pi}{2} \cdot \frac{2}{\pi} = 1 \] For the second term: \[ \frac{dy_2}{dx} = \frac{1}{2\sqrt{\frac{\pi}{2}}} = \frac{1}{2 \cdot \sqrt{\frac{\pi}{2}}} = \frac{1}{\sqrt{2\pi}} \] 3. **Combine the results**: Now we can combine the derivatives: \[ \frac{dy}{dx} = 1 + \frac{1}{\sqrt{2\pi}} \] ### Final Answer: Thus, the value of \( \frac{dy}{dx} \) at \( x = \frac{\pi}{2} \) is: \[ \frac{dy}{dx} = 1 + \frac{1}{\sqrt{2\pi}} \]
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OBJECTIVE RD SHARMA ENGLISH-DIFFERENTIATION-Chapter Test
  1. If y=sin^(-1){(5x+12 sqrt(1-x^(2)))/(13)}, find (dy)/(dx).

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  2. If f(x)=cos^(-1){(1-(log(e)x)^(2))/(1+(log(e)x)^(2))}, then f'( e )

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  3. y=sin^(-1)[sqrt(x-ax)-sqrt(a-ax)]

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  4. Let f(x)=(x^3+2)^(30) If f^n (x) is a polynomial of degree 20 where f^...

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  5. If f(x)=cos^(2)x+cos^(2)(x+(pi)/(3))+sinxsin(x+(pi)/(3)) and g((5)/(4)...

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  6. If f(x)=10cosx+(13+2x)sinx then f''(x)+f(x)=

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  7. Let a function f:RtoR satisfy the equation f(x+y)=f(x)=f(Y)AAx, yepsil...

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  8. If f(x)=log{(u(x))/(v(x))},\ u(1)=v(1) and u^(prime)(1)=v^(prime)(1)=2...

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  9. If f'(x)=arc tan((x^(x)-x^(-x))/(2)), then f'(1) is equal to

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  10. Let f(x)=2^(2x-1)" and "g(x)=-2^(x)+2xlog2. Then the set of points sat...

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  11. If y=logu|cos4x|+|sinx|,where u=sec2x find (dy)/(dx) at x=-pi/6

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  12. If f(4)= 4, f'(4) =1 then lim(x to 4) 2((2-sqrtf(x))/ (2 - sqrtx)) is ...

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  13. if 2x^2-3xy+y^2+x+2y-8=0 then (dy)/(dx)

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  14. If y=log{((1+x)/(1-x))^(1//4)}-(1)/(2)tan^(-1)x," then "(dy)/(dx)=

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  15. If x=costheta,y=sin5theta," then "(1-x^(2))(d^(2)y)/(dx^(2))-x(dy)/(dx...

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  16. If f : R - R is an even function which is twice differentiable on R an...

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  17. Observe the following statements: "I. If "f(x)=ax^(41)+bx^(-40)," ...

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  18. If x=e^tsint,y=e^tcost then (d^2y)/(dx^2) at x=pi is

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  19. The value of (dy)/(dx) at x=(pi)/(2), where y is given by y=x^(sinx)...

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  20. If 2^(x)+2^(y)=2^(x+y) then (dy)/(dx)is equal to

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