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Calculate y=4x-6 when x=3

Firstly we have an equation y=4x-6. We are given that x=3 and we want to find y. What we must do is substitute x=3 into the equation to get y: y=4(3)-6 =6

Answered by Sinan U. • Maths tutor

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Expand and simplify (3x^2 + 2)(2x + 5) – 6x(x^2 – 3)

First, multiply out 6x(x^2 - 3) so that it becomes – 6x^2 – 18xThen, multiply (3x^2 + 2) and (2x + 5) so that it becomes 6x^3 + 15x^2 + 4x + 10Add the two results above: 6x^3 + 15x^2 + 4x + 10 – 6x^3 – 18...

Answered by Ancel B. • Maths tutor

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The curve C has the equation y=((x^2+4)(x-3))/2*x where x is not equal to 0 . Find the tangent to the curve C at the point where x=-1 in the form y=mx+c

Firstly we need to expand out y into a series of terms to make it easier for us to compute the derivative . You multiply out the brackets to get y=(x³-3x²+4x-12)/2x then we divide ea...

Answered by Ellie M. • Maths tutor

12449 Views

Let z=x+yi such that 16=5z - 3z*, What is z?

z* is the complex conjugate of z therefore z* = x - yi. So 16 + 32i = 5(x + yi)-3(x - yi), real: 16 = 5x - 3x => 16=2x => x=8, imaginary: 32 = 5y + 3y => 32 = 8y => y=4, therefore z = 8 + 4i.<...

Answered by Ben C. • Maths tutor

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