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How do I plot a graph of y=x^3-9x?

To begin with we see that y=x 3 -9x is a positive cubic function, and therefore we know its general shape.The first step is to find the x interecepts. We do this by setting y=0 and solving the resulting equa...
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Answered by Tutor127548 D. • Maths tutor
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Nine-thousand five-hundred and forty-two people attend a pop concert. Round this number to the nearest hundred.

Answer: nine-thousand five-hundred (9,500) There are 9 thousands, 5 hundreds, four tens and 2 units. We need to round the hundreds and the answer we have in 5 hundreds. Because of there being 5 hundreds we n...
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Answered by Alexandra W. • Maths tutor
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expand (2x+4)(x+2)

For this question you can use a method called the foil method. The F stands for first therefore you times the 2 variables that are first in each bracket. 2x times x which gives you 2x^2. The O stands for out...
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Answered by Aiyshah F. • Maths tutor
5928 Views

Integrate the function 1/sqrt(9-x^2) with respect to x

Hint: Use the substitution x = 3sin(u)Method: substitute u into the function then times it all by dx/du. Simplify and integrate with respect to u to get u. Then resubstitute x back into the equation to get:A...
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Answered by Luke G. • Maths tutor
4451 Views

Given two coordinate points (a1,b1) and (a2,b2), how do I find the equation of the straight line between them?

Firstly, remember that we can write such a line in the form y = mx + c, where x and y are our two axes, m is the gradient of the line, and c is the y-axis intersection point. Given this general formula, we n...
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Answered by Lewis H. • Maths tutor
8332 Views