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Why is it that the sum of all natural numbers up to n is 1/2(n)(n+1)?

First let's consider the case of even numbers. Suppose n is even, then it must be double some other number, so we have: n = 2k Where k is another natural number. We want to find out what: 1 + 2 + ... + (n - ...
IM
Answered by Ibrahim M. Maths tutor
4758 Views

Find dy/dx in terms of t for the curve defined by the parametric equations: x = (t-1)^3, y = 3t - 8/t^2, where t≠0

The first step is to recognise that, by the chain rule, dy/dx = dy/dt * dt/dx. dy/dt and dt/dx can both be found by differentiating the functions given in the question, to give dy/dt and dx/dt. dt/dx is the ...
AC
Answered by Alex C. Maths tutor
21960 Views

integrate the following: 2x^4 - 4/sqrt(x) +3 with respect to x

The 3 terms of this equation can be integrated separately. The general integration of x n is (x n+1 )/n+1 where n is a real number not equal to -1. This can be applied to the terms 2x 4 , -4/sqrt(x) and 3 se...
AF
Answered by Adrien F. Maths tutor
4079 Views

Why is the derivative of the exponential function itself?

The exponential function is defined as a power series, which we may (for reasons that are beyond the scope of A-level) differentiate term by term to get another power series. The general term of the series d...
GB
Answered by George B. Maths tutor
5099 Views

evaluate the integral of lnx

this is an example of an integration by parts problem, we must use integration by parts to evaluate this integral;although this would not be entirely obvious as the integral does not seem to be the product o...
AR
Answered by Aaron R. Maths tutor
3516 Views