Multiplication of Polynoimals by Polynomials

Chapter 8 Class 8 Algebraic Expressions and Identities
Concept wise

### Transcript

Ex 8.4, 3 Simplify. (vii) (1.5π₯β4π¦)(1.5π₯+4π¦+3)β4.5π₯+12π¦Here, there are 2 expressions: First expression = (1.5π₯β4π¦)(1.5π₯+4π¦+3) Second expression = 4.5π₯+12π¦ Solving First expression (1.5π₯β4π¦)(1.5π₯+4π¦+3) = 1.5π₯(1.5π₯+4π¦+3)β4π¦(1.5π₯+4π¦+3) = (1.5π₯Γ1.5π₯)+(1.5π₯Γ4π¦)+(1.5π₯Γ3)β(4π¦Γ1.5π₯) β(4π¦Γ4π¦)+(4π¦Γ3) = (ππ/ππΓππ/ππ) π^π+(ππ/ππΓπ)ππ+(ππ/ππΓπ)πβ(πΓππ/ππ)ππ βπππ^π+πππ = (225/100) π₯^2+(60/10)π₯π¦+(45/10)π₯β(60/10)π¦π₯β16π¦^2+12π¦ = 2.25π₯^2+6π₯π¦+4.5π₯β6π¦π₯β16π¦^2+12π¦ = 2.25π₯^2β16π¦^2+4.5π₯β12π¦+6π₯π¦β6π₯π¦ = π.πππ^πβπππ^π+π.ππβπππ Now, our equation becomes (π.ππβππ)(π.ππ+ππ+π)βπ.ππ+πππ = 2.25π₯^2β16π¦^2+4.5π₯β12π¦β4.5π₯+12π¦ = 2.25π₯^2β16π¦^2+4.5π₯β4.5π₯β12π¦+12π¦ = π.πππ^πβπππ^π