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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
13886 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
6411 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
11408 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
4560 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
3689 Views