Polynomials Thursday, 31 October 2019
Long Division Example Work out each of the following a) 4095 12 b) 5595 15
Example Divide by
Example Divide by
Factor theorem Example What is the remainder when is divided by
Example What is the remainder when is divided by Example What is the remainder when is divided by
That is the remainder is P(a) Let P(x) be a polynomial in x to be divided by the linear function x – a Where Q(x) = Quotient R = Remainder Putting x = a That is the remainder is P(a) If R = 0 when P(x) is divided by (x – a) i.e. If P(a) = 0 then (x – a) is a factor of P(x)
Example Show that (x + 1) is a factor of the cubic and hence factorise completely
Example Show that (x – 2) is a factor of x3 – 4x2 + x + 6 Hence factorise completely x3 – 4x2 + x + 6 Solve the equation x3 – 4x2 + x + 6 = 0
Example Solve the equation
Past A – Level paper question a) When ax3 – 12x2 – 6x + 5 is divided by x + 1, the remainder is –3. Find the value of the constant a. b) Factorise 8x3 – 14x2 – 7x +6