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# (2x+1)(3xsquared-2x-5)

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(2x+1)(3xsquared-2x-5)

Guest Feb 11, 2015

#1
+1090
+10

When typing, use this notation for power "^2"

So we have:

(2x + 1)(3x^2 - 2x - 5)

Let's use the box method of multiplication for explanation:

3x^2    -2x      -5

2x | 6x^3 | -4x^2 | -10x

1   | 3x^2 | -2x     | -5

Since we've multiplied all of the terms using a box, now we can add them all together:

6x^3 + 3x^2 - 4x^2 -2x - 10x - 5

After combining like terms, we have: 6x^3 - x^2 -12x -5

Mathematician  Feb 11, 2015
#1
+1090
+10

When typing, use this notation for power "^2"

So we have:

(2x + 1)(3x^2 - 2x - 5)

Let's use the box method of multiplication for explanation:

3x^2    -2x      -5

2x | 6x^3 | -4x^2 | -10x

1   | 3x^2 | -2x     | -5

Since we've multiplied all of the terms using a box, now we can add them all together:

6x^3 + 3x^2 - 4x^2 -2x - 10x - 5

After combining like terms, we have: 6x^3 - x^2 -12x -5

Mathematician  Feb 11, 2015
#2
+92699
0

Thanks, Mathematician....I like that method !!!

CPhill  Feb 11, 2015
#3
+1090
+3

Yep, it's the first method my school taught me (just recently), but using distribution is less time consuming.

Mathematician  Feb 11, 2015
#4
+92699
+3

I dunno'...this method seems pretty "clean'.....you can follow the "diagonal" pattern to combine like terms......!!!

CPhill  Feb 11, 2015
#5
+1090
+3

It is definitely very accurate because of its display; however by "going down the line" in distribution, one can combine like terms in the same way.

It is a good method for teaching, but in practice, I use distribution.

Mathematician  Feb 11, 2015
#6
+18
0

i like the method. it seems kind of easier lol..

HappyBJ  Feb 11, 2015
#7
+92699
0

Yep...me, too.....HappyBJ.....!!!

CPhill  Feb 11, 2015
#8
+18
0

u mean BJ? LOL

HappyBJ  Feb 11, 2015
#9
+1090
0

I guess it's sort of a number sense mentality to want to problems faster rather than with accuracy and ease...

Academic U.I.L. is fine ingrained within my mind now.

Mathematician  Feb 11, 2015
#10
+3691
0

here i am again!

BrittanyJ  Feb 11, 2015
#11
+92699
0

I can't call you BJ....that one is "reserved" for BrittanyJ.....!!!!

I might use HBJ.....how does that sound???

CPhill  Feb 11, 2015
#12
+3691
0

hey, Mathematician! wat about "M&M" for nickname? LMAO!

BrittanyJ  Feb 11, 2015
#13
+3691
+3

BrittanyJ  Feb 11, 2015
#14
+92699
+3

Hey, Mathematician..you should feel honored..BJ just gave you your "forum name'...that OFFICIALLY accepts you into the "pack'  !!!

## MatheMatician  =  M & M   !!!!

CPhill  Feb 11, 2015
#15
+3691
0

Chris, have u figured out who HappyBJ is?

BrittanyJ  Feb 11, 2015
#16
+1090
0

That was nice... I think I'll accept that name (or that name will be accepted upon me for me.)

Mathematician  Feb 11, 2015
#17
+92699
+3

No clue.....maybe he's related to LBJ....!!!!

CPhill  Feb 11, 2015
#18
+3691
+3

same person, chris... same person LOL

BrittanyJ  Feb 11, 2015
#19
+94106
0

I have not seen mathematician's method before either but I do like it!!

Melody  Feb 11, 2015