Number and Algebra
Functions
Geometry & Trigonometry
Statistics & Probability
Calculus
Type: Long Answer | Level: - | Paper: -
Consider the function f(x)=xe−2xf(x) = x e^{-2x}f(x)=xe−2x.
Find expressions for the first three derivatives, f′(x)f'(x)f′(x), f′′(x)f''(x)f′′(x), and f′′′(x)f'''(x)f′′′(x).
Conjecture a general formula for the nnnth derivative, f(n)(x)f^{(n)}(x)f(n)(x), in terms of nnn and xxx.
Prove your conjecture by mathematical induction for all n∈Z+n \in \mathbb{Z}^+n∈Z+.
Prove by induction that for integer m≥n≥0m \ge n \ge 0m≥n≥0, the nnnth derivative of f(x)=(ax+b)mf(x)=(ax+b)^mf(x)=(ax+b)m is given by: f(n)(x)=an m(m−1)⋯(m−n+1) (ax+b)m−nf^{(n)}(x)=a^n\,m(m-1)\cdots(m-n+1)\,(ax+b)^{m-n}f(n)(x)=anm(m−1)⋯(m−n+1)(ax+b)m−n
By induction, derive the formula for the nnnth derivative of f(x)=x2e3xf(x)=x^2 e^{3x}f(x)=x2e3x.
Find the nnnth derivative of f(x)=x−1f(x)=x^{-1}f(x)=x−1 using mathematical induction.
Determine by induction the nnnth derivative of f(x)=xepxf(x)=x e^{px}f(x)=xepx and show that f(n)(x)=pn−1(px+n)epx.f^{(n)}(x)=p^{n-1}(px + n)e^{px}.f(n)(x)=pn−1(px+n)epx.
Prove by induction that for f(x)=xmf(x)=x^mf(x)=xm and integer 0≤n≤m0 \le n \le m0≤n≤m, f(n)(x)=m!(m−n)! xm−n.f^{(n)}(x)=\frac{m!}{(m-n)!}\,x^{m-n}.f(n)(x)=(m−n)!m!xm−n.
Find a general expression for the nnnth derivative of f(x)=sin(bx)f(x)=\sin(bx)f(x)=sin(bx).
Show by induction that the nnnth derivative of f(x)=cos(bx)f(x)=\cos(bx)f(x)=cos(bx) is f(n)(x)=bncos(bx+nπ2).f^{(n)}(x)=b^n\cos\left(bx+\frac{n\pi}{2}\right).f(n)(x)=bncos(bx+2nπ).
Prove by induction that for n≥1n\ge1n≥1, the nnnth derivative of f(x)=ln(x)f(x)=\ln(x)f(x)=ln(x) is f(n)(x)=(−1)n−1(n−1)!xn.f^{(n)}(x)=(-1)^{n-1}\frac{(n-1)!}{x^n}.f(n)(x)=(−1)n−1xn(n−1)!.
Show by induction that the nnnth derivative of f(x)=eaxf(x)=e^{ax}f(x)=eax is f(n)(x)=aneaxf^{(n)}(x)=a^n e^{ax}f(n)(x)=aneax
Previous
Question Type 3: Higher-order derivatives of functions with repeating patterns
Next
No next topic