Q. Given the function y=x−xsinx, find dxdy in any form.
Apply product rule: Apply the product rule to the term xsinx. 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, dxd(xsinx)=dxd(x)⋅sinx+x⋅dxd(sinx).
Differentiate x and sinx: Differentiate x and sinx separately.The derivative of x with respect to x is 1.The derivative of sinx with respect to x is cosx.So, sinx0 and sinx1.
Substitute derivatives into formula: Substitute the derivatives into the product rule formula.From Step 1, we have (dxd)(xsinx)=1⋅sinx+x⋅cosx.This simplifies to (dxd)(xsinx)=sinx+xcosx.
Differentiate entire function: Differentiate the entire function y=x−xsinx. The derivative of y with respect to x is the derivative of x minus the derivative of xsinx. So, dxdy=dxd(x)−dxd(xsinx).
Substitute derivatives into equation: Substitute the derivatives found in Steps 2 and 3 into the equation from Step 4.We have (dxdy)=1−(sinx+xcosx).This simplifies to (dxdy)=1−sinx−xcosx.
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