Mathematics

Mathematics

Problem

For y=xsin⁡xy = x\sin x, the value of y′(0)y'(0) is 00 even though ddx(x)\dfrac{d}{dx}(x) and ddx(sin⁡x)\dfrac{d}{dx}(\sin x) are both non-zero at x=0x=0. Which statement best explains this? a) Because both sin⁡0\sin 0 and cos⁡0\cos 0 are zero, the two terms in the product rule each evaluate to 00.},{ b) Since y(0)=0y(0)=0, any tangent drawn at the origin must be horizontal, so the derivative is 00.},{ c) In the expression for y′y', one term contains the factor xx, which becomes 00 at x=0x=0, making the whole sum 00.},{ d) Using the small-angle approximation sin⁡x≈x\sin x\approx x, the function becomes x2x^{2} near x=0x=0 whose derivative at 00 is 00.}]},

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