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A quantity N is increasing with respect to time, t. It is increasing in such a way that N = ae^(bt) where a and b are constants. Given when t = 0, N = 20, and t = 8, N = 60, find the value: of a and b, and of dN/dt when t = 12

N = ae^bt When N = 20, t = 0. We can substitute this in.20 = ae^{b x 0} ...

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How would you use the following expression to approximate [(4-5x)/(1+2x)(2-x)] when x=5 (A2 pure)

So I cant really answer this question over text however, the method would be using partial fractions to split the two fractions into two, then using a binomial expansion, but the indicies will be negative...

Answered by • Maths tutor

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How does E. E. Cummings present a critique of jingoism in his poem '"next to of course god america i'?

In '"next to of course god america i', E. E. Cummings presents a critique of empty rhetoric, specifically jingoistic rhetoric (evidenced by Cummings play on the phrase "by jingo"). All but ...

Answered by William H. • English tutor

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Find the stationary points of y= 5x^2 + 2x + 7

Stationary points occur when the gradient is 0 so when dy/dx =0 therefore we need to find dy/dx.By using 'down and decrease', we bring down the power and multiply by the coefficient and then decrease the ...

Answered by Alexandra M. • Maths tutor

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If y=4x^3+3/x^2-3, what is dy/dx?

We know the rule for differentiation is, multiply by the power reduce the power by one.
Although having several parts this looks confusing we just need to break it down.
4x^3 differentiates to 1...

Answered by • Maths tutor

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