Why is the inverse of a gradient -1/x?
Because the value, x and its inverse, -1/x should multiply together to give -1. This is proof that two lines are perpendicular (or having the same magnitude of gradient but opposite signs +/- ).
SR
Related Maths A Level answers
All answers ▸For a given function F(x), what does the graph of the function F(x+2) look like in comparrison to F(x)?
Functions: If f(x)=3x^2 - 4 and g(x) = x + 3, 1) Evaluate f(3), 2) Find the inverse of f(x) (f^-1(x)), 3)Find fg(x).
Use the geometric series formula to find the 9th term in this progression : 12 18 27...
Solve the following equation for k, giving your answers to 4 decimal places where necessary: 3tan(k)-1=sec^2(k)