Suppose is a cubic polynomial satisfying the following conditions:
MATHEMATICS · Subjective · A Level · Mathematics · Algebra and Functions · Algebra and Functions
Problem
Suppose P(x)=ax3+bx2+cx+d is a cubic polynomial satisfying the following conditions:
(i) (x+1) is a factor of P(x).
(ii) (x−2) is a factor of P(x).
(iii) When P(x) is divided by x−3, the remainder is 5.
(a) Form three equations in a, b, c, and d based on the above information.
(b) Given that a=1, solve the equations to determine b, c, and d.
(c) Using the complete polynomial obtained, factorise P(x) completely over the real numbers.
(d) Write the roots of the equation P(x)=0.
Provide detailed solutions for each part.