Question

19. If p(x) = 3x^2 - 4 and r(x) = 2x^2 - 5x+1 find -5r*(2a)

Answer 1

We have two polynomials:

$\begin{gathered} p(x)=3x^2-4 \\ r(x)=2x^2-5x+1 \end{gathered}$

We have to find -5*r*(2a). This can be written as:

$-5\cdot r\cdot(2a)=(-5\cdot2a)\cdot r=-10a\cdot r$$\begin{gathered} -10a\cdot r(x)=-10a\cdot(2x^2-5x+1) \\ -10a\cdot2x^2-10a(-5x)-10a\cdot1 \\ -20ax^2+50ax-10a \end{gathered}$

Answer: -5r(2a) = -20ax^2+50ax-10a