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a) Integrate ln(x) + 1/x - x to find the equation for Curve A b) find the x coordinate on Curve A when y = 0.

a) Integrate ln(x) by parts: u = ln(x), dv/dx = 1, du/dx = 1/x, v = x int(u dv/dx) = u v - int(du/dx * v) = ln(x)/x - x so int(ln(x) + 1/x - x) = ln(x)/x - x + ln(x) + x^2 + Cb) y = ln(x)/x - x + ln(x) + x^2...
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Answered by Ellie N. Maths tutor
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Use integration by parts to evaluate: ∫xsin(x) dx.

Since our function is a product of two "mini-functions" of x, we are able to use integration by parts.The trick for this is to correctly set 'u' and 'dv'. 'u' should be labelled as the function whi...
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Answered by Bailey A. Maths tutor
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Factorise 5x^2 + 20x

Factorising is a way of simplifying an equation by putting it into common parts. In the equation above we can see that x is common to both the 5x^2 and the 20x. If we divide by x and put this in-front of the...
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Answered by Dominic C. Maths tutor
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Find where the equation y = x^2 + x - 2 crosses the x-axis.

First, notice that any equation crosses the x-axis when y = 0.Second, notice that x 2 + x - 2 = 0 is an example of a quadratic equation. So, we generally do 1 of 3 things (Factorise, Complete the square or u...
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Answered by Asad R. Maths tutor
3217 Views

Use the factor theorem to show that (x+2) is a factor of g(x)= 4x^3 - 12x^2 - 15x + 50

To prove (x+2) is a factor, the value of x that makes x+2 equal 0 must be substituted into the function g(x) also making g(x)=0. In this case, the value of x being -2 makes x+2 equal to 0 and when substitute...
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Answered by James R. Maths tutor
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