Graphs Flashcards
What do we need to draw a decent graph
Points of intersect with x and y axis, asymptotes and stationary points.
Domain and range
Finding intersection with y axis
Set x = 0 may need to find a limit
Finding intersection with x axis
set y = 0 likely have to solve a quadratic or higher: use long algebraic division
Finding asymptotes
Find value at infinity or values of discontinuity (potential vertical asymptotes
Finding stationary points
Occur when f’(x) = 0
Determining nature of stationary points
Use 2nd order or higher derivatives of the function at our desired points.
For n where f^n(x)=0 and f^(n+1)(x) ≠ 0
If n is odd: <0 max, >0 min
If n is even: < 0 decreasing inflection, >0 increasing inflections
Domain and range
Can be determined from previously but draw them in graph
What does a stationary point of inflection look like
A point where gradient = 0 but the ‘direction’ doesn’t invert