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How do you find (and simplify) an expression, in terms of n, for the sum of the first n terms of the series 5 + 8 + 11 + 14 + ... ?

Normally, this would be quite hard! We'd have to play around with the sequence and try different formulas until something worked. Luckily, this is what we call an "Arithmetic Series". That's becaus...
MS
Answered by Matthew S. • Maths tutor
19641 Views

What is dy/dx when y=ln(6x)?

This is a common question on A2 Maths papers as it tests both the ability to use the chain rule and the ability to differentiate natural logarithms. y = ln(6x) Alarm bells should start ringing whenever a que...
EM
Answered by Eleanor M. • Maths tutor
13729 Views

Using mathematical induction, prove De Moivre's Theorem.

De Moivre's theorem states that (cosø + isinø) n = cos(nø) + isin(nø). Assuming n = 1 (cosø + isinø) 1 = cos(1ø) + isin(1ø) which is true so correct for n = 1 Assume n = k is true so (cosø + isinø) k = cos(k...
SE
Answered by Scott E. • Maths tutor
82956 Views

How do I integrate 3^x?

First I would ask what have they tried, and see if any of their attempts are on the right track - and then guide them from there, if not: 3^x is quite a difficult form to deal with, so is there any other way...
JW
Answered by Josh W. • Maths tutor
26989 Views

Why do we need the constant of integration?

Say that we have a differentiated equation f'(x), and we want to find the orginal equation f(x) from this. We would have to use integration, as differentiation and integration are the reverse of each other. ...
EM
Answered by Eleanor M. • Maths tutor
6317 Views