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Factorise x^2 - 7x + 12 = 0

Method 1) Find two numbers which multiply to 12, and who’s sum is -7. ( This could be done by writing out the factors of 12, and seeing which add to -7.) From doing this we get -3 and -4, therefore our answe...
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Answered by Rachel S. • Maths tutor
24615 Views

How do you differentiate?

Say you have the term y=3X 2 . You start by bringing the power down and placing it in front of the 3 so they multiply like so y=2x3X 2 then next you take one away from the power like so y=2x3X 1 . This can t...
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Answered by Alex Y. • Maths tutor
3833 Views

Solve 4(x-5)=3x-6

First, expand brackets to make your life easy. So you would do 4 times x and 4 times -5 to give u 4x-20. Then gather all the x's on one side of the equation and numbers on the other side. 4x-20=3x-6. Remembe...
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Answered by Aymen S. • Maths tutor
5525 Views

p(x)=2x^3 + 7x^2 + 2x - 3. (a) Use the factor theorem to prove that x + 3 is a factor of p(x). (b) Simplify the expression (2x^3 + 7x^2 + 2x - 3)/(4x^2-1), x!= +- 0.5

(a) The factor theorem states that: the polynomial f(x) has a factor (x - a) if and only if f(a) = 0.Use that information, we know that (x + 3) is a factor of p(x) if p(-3) = 0. So let's test it:p(-3) = 2(-3...
JM
Answered by James M. • Maths tutor
11491 Views

There are a collection of CDs. There are 2 Rock CDs, x Pop CDs and 2x + 5 Jazz CDs. A CD is chosen at random, the probability that it is Rock is 1/20. Work out the probability it is Jazz.

To answer this question first we need to work out how many CDs we have in total. We do this by adding up the number of CDs in each category:Total = 2 + x + 2x + 5. We can simplify this to give:Total = 3x + 7...
JM
Answered by James M. • Maths tutor
9174 Views