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Differentiate 3x^2 + 4x - 7

In order to differentiate a number, 2 steps are needed to be made. The first is to reduce the power of the number by 1 and then multiply that value to the first number. I will run you through the given quest...
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Answered by James R. • Maths tutor
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Find the positive solution to the equation (x^2+9x+18)/(x^2-9)=10

If we first factorise the top and the bottom of the equation we can see that the top is equal to (x+6)(x+3) and the bottom is (x-3)(x+3). This means we can divide the top and bottom by (x+3) giving us a resu...
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Answered by Joseph R. • Maths tutor
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Sketch a graoh of current against potential difference for a filament lamp and explain its shape.

(draw diagram on whiteboard) As the potential difference increases, the current increases, since V=IR (where V is the potential difference, I is the current and R is the resistance). Initially the current in...
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Answered by Tamanna D. • Physics tutor
3002 Views

Explain how the photoelectric effect gives evidence for the photon theory of light.

When light is shone onto a piece of metal, if the light is below a certain frequency, no photoelectrons are emitted. Only if the light is above a certain frequency, known as the threshold frequency, are phot...
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Answered by Tamanna D. • Physics tutor
10885 Views

(e*sqrt(e))/cuberoot(e^2)=e^k find k

This an indices question. What you need to do is simplify the left hand side so that you have e to some power and that will give you k. You can start with the rule that square roots and cube roots are 1/the ...
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Answered by Tamanna D. • Maths tutor
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