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Express x^2-7x+2 in the form (x-p)^2+q where p and q are rational. Hence or otherwise find the minimum value of x^2-7x+2

For the first part, use the 'complete the square method', which gives (x-7/2) 2 -49/4+2, simplified to (x-7/2) 2 -41/4. To find the answer for the second part, set x=7/2 so that the bracketed part becomes 0,...
CW
Answered by Connaire W. • Maths tutor
5345 Views

An isotope of 238,92-Uranium decays into a stable isotope of 206,82-Lead through a series of alpha and beta decays, how many of each does it go through?

This is a good example of where simplification can make an otherwise tricky question a lot easier. It is easy to get confused trying to work out different isotopes and the extra products of the decays, but a...
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Answered by Nathan M. • Physics tutor
6100 Views

What is the difference between "est", "es" and "et"?

We can classify these words in two categories, verbs for "est" and "es" which are the conjugaison of the verbe "être" = "be". "est" is use when the subject c...
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Answered by Lucile O. • French tutor
83025 Views

Explain why the average and marginal revenue curves for a perfectly competitive firm are horizontal while those of a monopoly slope downwards.

The average revenue curve for a perfectly competitive firm is horizontal due to the fact that it faces perfectly elastic demand at the market determined price. This is because there is a significant amount o...
JS
Answered by James S. • Economics tutor
50826 Views

Find the binomial expansion of (2+x)^3

We know thst the binomial expansion formula is (1+x) n = 1+nx +(n)(n-1)(x 2 )/2! ...etc Thus we want to rearrange the expression we are given into the form (1+x) n so that we can apply the formula to it. Tak...
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Answered by Laura V. • Maths tutor
11406 Views