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Why does the constant disappear when differentiating a function?

We can think of the constant term in a function in terms of x, for example in x^2 + 3x + 2 as 2 being multiplied by x^0. Anything to the power of 0 is equal to one, so in our example we would have 2 * x^ 0 w...
AP
Answered by Abdullah P. Maths tutor
13591 Views

Factorise: y = x^2 + 5x + 6

With quadratic equations, there are two ways in which to answer Firstly (and most simply), look for two numbers that multiply to make c and add up to make b in the equation y = ax 2 + bx + c , so in the exam...
AN
Answered by Adnan N. Maths tutor
6277 Views

Can you show me why the integral of 1/x is the natural log of x?

We can break this down into steps, going deeper each time. First we might just say: well, since integration is fundamentally the inverse process of differentiation and we know that the derivative of ln(x) is...
JL
Answered by James L. Maths tutor
11156 Views

How do you expand brackets?

Let's have a look at a pair of brackets: (a+b)(c+d)To expand these brackets each value in one bracket must be multiplied by all values in the other bracket separately then added together. So we have: ac+ad+b...
PB
Answered by Phoebe B. Maths tutor
4472 Views

why is (x+y)^2 ≠ x^2 + y^2

Because if we simply expand (x+y) 2 we'd get x 2 +y 2 +2xy which shows that there's an extra term which is 2xy. another practical way to check your work and see why LHS ≠ RHS is by substituting random number...
JH
Answered by Jamal H. Maths tutor
3585 Views