Top answers


Prove the change of base formula for logarithms. That is, prove that log_a (x) = log_b (x) / log_b (a).

Firstly, recall the definition of a logarithm: if y = log a (x), then this means that y is the power you have to raise a to, to get x, that is a y = x.Now, we want to introduce a new base, b. Let's take log ...
TH
Answered by Tom H. Maths tutor
14080 Views

(ii) Prove by induction that, for all positive integers n, f(n) = 3^(3n–2) + 2^(3n+1) is divisible by 19

Let P(n) represent the statement that 'f(n) is divisible by 19'. For the basis step, I prove that P(1) is true: f(1) = 3 3(1)-2 + 2 3(1)+1 = 19. 19 is divisible by 19 so P(1) is true. I now want to prove tha...
DL
Answered by Daniel L. Maths tutor
10889 Views

How do you find stationary points of an equation, eg. y=x^2+3x+2

Stationary points of an equation are found where the gradient of the tangent at this point equals zero. A diagram can illustrate this. To find them differentiate the given equation (which gives the gradient)...
EC
Answered by Ellie C. Maths tutor
3866 Views

Find the equation of the tangent to: y = X^2 + 3x + 2 at the point (2,12)

(1) Find the gradient using differentiation (2) If the gradient at (x 1 ,y 1 ) is m,y - y 1 = m(x - x 1 ) (1) We differentiate the given equation:dy/dx = 2x + 3 Then, find the gradient at (2,12). Sub x= 2 in...
SC
Answered by Samuel C. Maths tutor
4572 Views

Given the equation 0=5x^2+3xy-y^3 find the value of dy/dx at the point (-2,2)

To answer this we will use implicit differentiation with respect to x. So start by differentiating each term. On the left hand side 0 differentiates to 0. On the right hand side 5x 2 differentiates to 10x. B...
HW
Answered by Holly W. Maths tutor
4189 Views