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Find the derivative and following function and hence find the value of coordinates for when the function is at a stationary point:

y = e x x 2 + e x : The derivative can be found using the chain rule. (A reminder of the chain rule: if y is a product of two functions of x i.e if y = F(x)G(x) , the derivative is as follows: y I = F I (x)G...
MC
Answered by Michael C. • Maths tutor
3903 Views

Why does exp(x+y) NOT equal exp(x)+exp(y)? [A-level Maths and Further Maths common mistake]

This is a very common mistake, so don't worry. To see why this is the case, let's go back through our notes to the "laws of indices" and recall the rule for adding powers; a m * a n = a (m+n) The e...
TD
Answered by Tutor56252 D. • Maths tutor
10029 Views

Solve the following equation by completing the square: x^2 + 6x + 3 = 0.

Completing the square is a method of solving quadratic equations that cannot be easily factorised, without having to use the quadratic formula. The first step is to look at the coefficient of the second term...
EC
Answered by Emma C. • Maths tutor
26839 Views

How do I remember the coefficients of a Taylor expansion?

If it's not sticking in your head; don't. I find it's easier to just remember what the point of a Taylor expansion is: to express a function as an infinite polynomial, often because polynomials are easy to d...
SR
Answered by Steven R. • Maths tutor
5219 Views

Given log3(3b + 1) - log3(a-2) = -1 for a > 2. Express b in terms of a.

We can start by recognising one of our properties of log. That is log a (x) - log a (y) = log a (x/y). Performing this on our question we get: log 3 ((3b+1)/(a-2)) = -1. Now we can remove our log and rewrite...
JW
Answered by Jason W. • Maths tutor
15942 Views