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Given the function y=xxsinxy=x-x\sin x, find dydx\frac{dy}{dx} in any form.

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Q. Given the function y=xxsinxy=x-x\sin x, find dydx\frac{dy}{dx} in any form.
  1. Apply product rule: Apply the product rule to the term xsinxx \sin x. The product rule states that the derivative of a product of two functions is the derivative of the first function times the second function plus the first function times the derivative of the second function. So, ddx(xsinx)=ddx(x)sinx+xddx(sinx)\frac{d}{dx}(x \sin x) = \frac{d}{dx}(x) \cdot \sin x + x \cdot \frac{d}{dx}(\sin x).
  2. Differentiate xx and sinx\sin x: Differentiate xx and sinx\sin x separately.\newlineThe derivative of xx with respect to xx is 11.\newlineThe derivative of sinx\sin x with respect to xx is cosx\cos x.\newlineSo, sinx\sin x00 and sinx\sin x11.
  3. Substitute derivatives into formula: Substitute the derivatives into the product rule formula.\newlineFrom Step 11, we have (ddx)(xsinx)=1sinx+xcosx(\frac{d}{dx})(x \sin x) = 1 \cdot \sin x + x \cdot \cos x.\newlineThis simplifies to (ddx)(xsinx)=sinx+xcosx(\frac{d}{dx})(x \sin x) = \sin x + x \cos x.
  4. Differentiate entire function: Differentiate the entire function y=xxsinxy = x - x \sin x. The derivative of yy with respect to xx is the derivative of xx minus the derivative of xsinxx \sin x. So, dydx=ddx(x)ddx(xsinx)\frac{dy}{dx} = \frac{d}{dx}(x) - \frac{d}{dx}(x \sin x).
  5. Substitute derivatives into equation: Substitute the derivatives found in Steps 22 and 33 into the equation from Step 44.\newlineWe have (dydx)=1(sinx+xcosx)(\frac{dy}{dx}) = 1 - (\sin x + x \cos x).\newlineThis simplifies to (dydx)=1sinxxcosx(\frac{dy}{dx}) = 1 - \sin x - x \cos x.

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