What are the roots of y=x^2+5x+6 ?
Roots = where line touches x-axis. Set equation equal to 0 as y=0 at the x-axis. Now we need to solve for the x values at which y=0. Quadratic is now 0=x^2+5x+6. Factorise quadratic: 0=(x+3)(x+2). Now you can divide the zero by either (x+3) or (x+2). Both are possibilities and cannot be ignored. Hence two equations are 0=x+3 and 0=x+2. Rearrange now to find that x=-3 and x=-2 when y=0. You have now found the roots of the equation.
SW
Related Maths A Level answers
All answers ▸Find the turning points of the curve (x^3)/3 + x^2 -8x + 5
Find the tangent for the line y=x^3+3x^2+4x+2 at x=2
How can I get better at Mathematics? I am struggling with confidence and achieving low grades.
A curve C has equation y = x^2 − 2x − 24sqrt x, x > 0. Prove that it has a stationary point at x=4.