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Expand and simplify fully 4(x - 2) - 2(3 - 5x)

Firstly, expand out the first bracket - 4x - 8 - 2(3 - 5x) Then the second bracket (remember a minus x a minus = a positive) - 4x - 8 - 6 + 10x Then finally group the like terms together - 4x + 10x - 8 - 6 =...
CR
Answered by Calum R. • Maths tutor
6193 Views

The curve y = 4x^2 + a/ x + 5 has a stationary point. Find the value of the positive constant a given that y-ordinate of the stationary point is 32.

This question might look hard but can be easily answered by breaking it down into steps and remembering a few key things. The first step is to recognise that the question is mentioning a stationary point whi...
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Answered by Helen B. • Maths tutor
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Rearrange y=(3x+5)/x to make x the subject

This question is asking us to make x the subject, so we’re aiming to end up with just x on its own on one side of the equation. Firstly, we need to get rid of the x on the bottom of the right-hand side, so t...
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Answered by Chloe K. • Maths tutor
8376 Views

Solve to find sin x , 4cos^2 + 7sin x -7 =0

4cos 2 x + 7 sinx - 7 =0 we know that sin 2 + cos 2 = 1 so 4(1-sin 2 x) + 7sinx -7 = 0 if we times out the brackets -4sin 2 x + 7 sinx -3 =0 4sin 2 x -7sinx +3 =0 (4sinx-1)(sinx +2)=0 so therefore sinx =1/4 ...
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Answered by Jo P. • Maths tutor
4152 Views

Find a and b (both real) when (a+b*i)^2=i.

Every complex number has a real and imaginary part. For the complex number z=a+bi the notation for real and imaginary parts respectively are Re(z)=a and Im(z)=b . If you know this, many complex algebra equat...
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Answered by Urte A. • Maths tutor
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