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Let f(x) = 3x^4 - 8x^3 - 3. Find the x- values of the stationary points of this function.

Stationary points occur when f'(x) = 0. To find this, we differentiate f(x) to get f'(x) = 12x^3 - 24x^2. We know that at the stationary points are when f'(x) = 0. so we know that 12x^3 - 24x^2 = 0. We can f...
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Answered by Yathavan S. • Maths tutor
3681 Views

Celine has £5 to buy pens and rubbers. Pens are 18p each. Rubbers are 30p each. She says “I will buy 15 pens. Then I will buy as many rubbers as possible. With my change I will buy more pens.” How many pens and how many rubbers does she buy? [5 marks]

Answer: 16 pens and 7 rubbers
AR
Answered by Ardra R. • Maths tutor
3208 Views

x^2 = 4(x – 3)^2

This is a quadratic equation, which contains terms up to x 2 . All quadratic equations can be written in the form a x 2 + b x + c = 0 where a , b and c are numbers, and a cannot be equal to zero. Expand the ...
JW
Answered by Jennifer W. • Maths tutor
4527 Views

Solve 10(x + 2) – (2x – 9) = 30

10(x+2) -(2x-9)=30; 10x+20-2x+9=30 paying attention to the sign change when solving the brackets; 8x+29=30; 8x=1 separating in order to find out x; x=1/8
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Answered by Cristian E. • Maths tutor
5078 Views

Factorise and simplify (6x-42)/((x^2)-49)

When we factorise, we are trying to put a long expression into a couple of brackets to make it neater and easier to work with. It is the opposite to multiplying out brackets. To start off with, we will facto...
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Answered by Robert S. • Maths tutor
5896 Views