29-06-2012, 10:03 PM
(This post was last modified: 29-06-2012, 11:19 PM by ssparikshya.)

hi friends, today i gonna show how to multiply binomial by a trinomial in 5 secs

Example : (X+2) (X^2 + 3X +2)

Step 1: multiply the 1st term of each polynomial to get the 1st term of the answer..

Answer : (X)^3+ ------- + -------- + --------- ; X Multiplied with X^2

Step 2: Multiply the last term of each polynomial to get the last term of the Answer..

Answer: (X)2 + --------- + --------- + 4; 2X2 = 4

Step 3 : Rainbow Multiply the First 2 Terms of each Polynomial to get the first middle term of The

Answer

Answer: (X)^3 + 5(X)^2 + ---------- + 4 ; 3(x)^2 + 2(x)^2

Step 4 : Rainbow Multiply the Last 2 Terms of each Polynomial to get the Last middle term of The Answer

Answer: (X)^3 + 5(X)^2 + 8X + 40

Normal way

(X+2) (X^2 + 3X + 2)

= X(X^2 + 3X + 2) + 2 ((X)^2 + 3X + 2)

= (X)^3 + 3(X)^2 + 2X + 2(X)^2 + 6X + 4

= (X)^3 + 5(X)^2 + 8X + 4

SOURCE : My Experiment