P- Differentiation (quadratics) ED Flashcards
What is the differentiation formula when y=ax?
dy/dx = (na)x power of n-1
How do you get 1/a to the power of m out of a fraction?
Becomes 1am to the power of -1
(Multiply top and bottom, to the power of negative n)
What are 4 things to do when differentiating harder expressions?
1) Turn roots into powers
2) Split up fractions
3) Expand brackets out
4) Beware of numbers in denominators
How do you differentiate from 1st principles?
1) Make a new coordinate with +h added on to original coordinate numbers
2) Put the coordinates into Δy / Δx
3) Simplify till all h’s are gone and you have a gradient
What goes to the left of the equation when differentiating from 1st principles?
lim
h→0
How do you find an equation of a tangent?
1) Get gradient by subbing x value into differentiated equation
2) Work out y value by subbing x into original equation
3) Sub all values into y-y1=m(x-x1)
What is an increasing function?
When the gradient is at least 0
f’(x)≥0 for all x values
What is a strictly increasing function?
When the gradient is greater than 0
f’(x)>0 for all x values
What is a decreasing function?
When the gradient is less than 0
f’(x)<0