(Original post by Candit)
The Curve y= (10/2x+1) -2 intersects the x-axis at A, The tangent to the curve at A intersects the y-axis at C.
i) Show that the equation of AC is 5y + 4x = 8
ii) Find the distance AC
do i differentiate it twice?
Set y=0, to find the x-coordinate of A.
Differentiate y = 10/(2x+1) -2 and sub in the x-coordinate of A, to get the gradient at A.
Use the coordinates of A and the gradient obtained to find the equation of tangent at A.
Set x=0 in the equation of tangent at A, to find the y-coordinate of point C.
Now find the gradient of AC, by using , then form an equation.