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Factorising and Expanding Brackets

Factorising equations: Lets look at the example: Factorise 3x+21 In order to factorise this equation, we need to find a common factor of both 3x and 21. For this equation, the common factor is 3 and so this ...
HM
Answered by Hannah M. • Maths tutor
9574 Views

How do you differentiate y = 5 x^3 + 1/2 x^2 + 3x -4

FIrslty to avoid confusion: x = the variable x X = multiplication. When you differentiate an equation, the derivative (answer) is referred to as dy/dx. For a polynomial as in this question you take each term...
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Answered by Emma M. • Maths tutor
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When using the addition rule in probability, why must we subtract the "intersection" to find the "union" with the Addition Rule?

There is a subtle point to be made here, which comes down to double counting. The addition rule:Pr(A union B) = Pr(A)+Pr(B)-Pr(A intersection B)allows us to work out the probability that either event A or ev...
LG
Answered by Lewis G. • Maths tutor
29759 Views

How do I find the minimum or maximum of a quadratic function?

Take a general function f(x) = ax²+bx+c First thing to do with every problem is sit back and think a bit: there are usually several ways to solve a problem but one will likely be easier and shorter. In this ...
MV
Answered by Max V. • Maths tutor
6330 Views

How do you know how many roots a quadratic equation has?

To work out the number of roots a qudratic ax 2 ​+bx+c=0 you need to compute the discriminant (b 2 ​-4ac). If the discrimant is less than 0, then the quadratic has no real roots. If the discriminant is equal...
LC
Answered by Lizzie C. • Maths tutor
82487 Views