MEDIUM
AS and A Level
IMPORTANT
Earn 100

By sketching graphs of y=ex and y=x+6, determine the number of roots of the equation ex-x-6=0.

Important Questions on Numerical Solutions of Equations

MEDIUM
AS and A Level
IMPORTANT
Show graphically that the equation 2x=x+4 has exactly two roots.
HARD
AS and A Level
IMPORTANT
By sketching two suitable graphs on the same diagram, show that the equation cotx=x2 has one root between 0 and π2 radians.
HARD
AS and A Level
IMPORTANT
By sketching a suitable pair of graphs, deduce the number of roots of the equation x=tan2x for 0<x<2π.
MEDIUM
AS and A Level
IMPORTANT

The equation x-0.5e3x=1 has a root α.

Show, by sketching the graph of y=e3x and one other suitable graph, that α is the only root of this equation.

MEDIUM
AS and A Level
IMPORTANT
By sketching a suitable pair of graphs, show that the equation x3+10x=x+5 has only one root that lies between 0 and 1¯.
EASY
AS and A Level
IMPORTANT

The equation x4-1-x=0 has a root, α, between x=1 and x=2.

Show that α also satisfies the equation x=1+x4.

MEDIUM
AS and A Level
IMPORTANT

The equation x4-1-x=0 has a root, α, between x=1 and x=2.

Show that α also satisfies the equation x=1+x4.

Write down an iterative formula based on the above equation 

Use your iterative formula, with a starting value of x1=1.5, to find α correct to 2 decimal places. Give the result of each iteration to 4 decimal places.

EASY
AS and A Level
IMPORTANT

The equation cosecx=x2 has a root, α, between 1 and 2 . The equation can be rearranged either as x=sin-11x2 or x=1sinx.

Write down two possible iterative formulae, one based on each given rearrangement.