Top answers

Given that y=x^3 +2x^2, find dy/dx . Hence find the x-coordinates of the two points on the curve where the gradient is 4.

First of all we are asked to differentiate the function. This can be easily done by multiplying the coefficient of x by its exponent, and then decreasing the exponent by one. Therefore, dy/dx=3x^2+4x We are ...
IH
Answered by Imran H. • Maths tutor
16538 Views

find dy/dx for the equation y = 6x ^(1/2)+x+3

Here you are being asked to differentiate. When differentiating, you times the value of x by its power and then subtract 1 from the power. So for this question you times 6x^(1/2) by 1/2 and then subtract 1 f...
GB
Answered by George B. • Maths tutor
5644 Views

How do you find the angle between two vectors?

Using cosine rule a.b = |a||b|cos(theta) and the example vectors a = (1,2,3) and b = (3,2,1),First explain why the cosine rule exists, use a geometric proof of the cosine rule. Show the magintude of a=b=root...
OB
Answered by OWEN B. • Maths tutor
3724 Views

How do you use factor theorem to show an algebraic term is a factor of a polynomial?

For example show that x + 3 is a factor of p(x) = x 3 - 5x 2 - 8x + 48 We need to show that when x = -3, p(x) = 0. If this is the case then x + 3 is a factor of p(x) putting x = -3 into the polynomial we obt...
ET
Answered by Elliot T. • Maths tutor
4343 Views

How come x^2 = 25 has 2 solutions but x=root(25) only has one? Aren't they the same thing?

(This is something that I didnt fully understand for quite a while at school.) So when we are solving x 2 =25, in order to get x "on it's own" we square root both sides. However the definition of r...
DJ
Answered by Dylan J. • Maths tutor
9185 Views