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A curve has equation y = 20x −x2 −2x3 . (A) Find the x-coordinates of the stationary points of the curve.

Firstly, differentiate the equation to find dy/dx.
dy/dx = 20 - 2x - 6x²
As dy/dx represents the gradient, we know that for a stationary point the gradient must be zero, hence for the...

Answered by Bradley W. • Maths tutor

5331 Views

Show that (x + 1)(x + 2)(x + 3) can be written in the form ax3 + bx2 + cx + d where a, b, c and d are positive integers.

lets expand the first two brackets first, so x * x gives x², x * 2 gives 2x, x * 1 gives x and 1 * 2 = 2. 2x and x are both in terms of x so we add these together to get 3x, giving us the quadr...

Answered by Annunzia C. • Maths tutor

26078 Views

f(x) is defined by f(x) = 3x^3 + 2x^2 - 7*x + 2. Find f(1).

f(1) = 31^3 + 21^2 - 7*1 + 2 = 3 + 2 - 7 + 2 = 0

Answered by Dragos M. • Maths tutor

2670 Views

What is 16^(3/2)

The rule for simplifying indices is to take them one at a time, so separate the problem into 16^(1/2)^3, which is 4^3, which is 64.

Answered by Jonah B. • Maths tutor

2921 Views

A curve has equation y = 20x - x^2 - 2x^3 . The curve has a stationary point at the point M where x = −2. Find the x- coordinate of the other stationary point of the curve

A stationary point on a curve is when the differential of the equation of the curve = 0. In other words when dy/dx = 0Take the equation in the question: y = 20x - x² - 2x³A simple ru...

Answered by Henry J. • Maths tutor

3380 Views