The polynomial p(x) is given: p(x)=x^3+2x^2-5x-6, express p(x) as the product of three linear factors

p(x)=x3+2x2-5x-6

      =x(x2+2x-5)-6

      =x(x2+2x+1-6)-6 as we know (x+1)2=x2+2x+1,5 can be expressed 1-6

      =x[(x+1)2-6]-6

      =x(x+1)2-6x-6

      =x(x+1)2-6(x+1)

      =(x+1)[x(x+1)-6]

      =(x+1)(x2+x-6) here, -6 can be expressed as -2*3, and -2+3=1 

      =(x+1)(x+3)(x-2)

 

JB

Related Maths A Level answers

All answers ▸

Differentiate y = x^2 - 2x-3 + e^3x + 2ln(x)


sin(x)/(cos(x)+1) + cos(x)/(sin(x)+1) = 1


Find the intergral of 2x^5 - 1/4x^3 - 5 with respect to x.


A tunnel has height, h, (in metres) given by h=14-x^2 where x is the horizontal distance from the centre of the tunnel. Find the cross sectional area of the tunnel. Also find the maximum height of a truck passing through the tunnel that is 4m wide.