Porisma

A hint to get started

Read polynomial roots as intersection inputs

The curve CC has equation y=x2−2x+2x+1y=\dfrac{x^2-2x+2}{x+1}.

(i) Determine the asymptotes of CC.

(ii) Sketch CC, showing clearly any axial intercepts, turning points and asymptotes.

(iii) Deduce the number of real roots of the equation x4−2x3+2x2−x−1=0x^4-2x^3+2x^2-x-1=0.

CJC · Lecture · Example 12

Rearrange the quartic so one side is the equation of C. Track inputs excluded by division.

Read the worked solution