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Given that y = 16x + x^(-1), find the two values of x for which dy/dx = 0

The first thing required is to find out what dy/dx is in terms of x. For this, we need to differentiate y with respect to x which be can so to each term of the polynomial. All you need to do is mutiply the t...
JM
Answered by James M. • Maths tutor
7992 Views

There is a cube with a length 3x. The expression for the volume in cubic centimeters is equal to the expression for the surface area in square centimeters. Calculate the length of a side of the cube.

volume = SA (3x) 3 = (3x) 2 x 6 27x 3 = 9x 2 x 6 27x 3 = 54x 2 27x = 54 27x - 54 = 0 27(x - 2) = 0 x - 2 = 0 x = 2 The question asks for the length which we are told is 3x: length => 3x = 3 x 2 = 6cm.
SD
Answered by Sofia D. • Maths tutor
7437 Views

Find ∫(x^3+x^2+6)dx.

∫(x 3 +x 2 +6)dx= ∫x 3 dx +∫x 2 dx+∫6dx =x 4 /4 +x 3 /3 +6x+C.
GI
Answered by Georgiana I. • Maths tutor
6559 Views

How do you 'complete the square' of a quadratic equation?

To complete the square, we need to rearrange the quadratic equation in the form of ax 2 + bx + c into the form r(x + p) 2 + q, where our task is to find the values of the unkowns of r, p and q. Let's take th...
RB
Answered by Ryan B. • Maths tutor
3562 Views

Using the trigonometric identity (sinx)^2 + (cosx)^2 = 1, show that (secx)^2 = (tanx)^2 + 1 is also a trigonometric identity.

We can divide by (cosx)^2 across the identity (sinx)^2 + (cosx)^2 = 1 (which can be derived from properties of the unit circle and a bit of Pythagoras’ theorem) to achieve [(sinx)^2 / (cosx)^2] + [(cosx)^2 /...
AB
Answered by Annie B. • Maths tutor
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