this is kind of embarrassing but can someone help me with year9 maths (1 Viewer)

[notrealemily]

i don't really understand the whole concept of binomial products :c


(i know pretty much everyone thinks 'lel algebra is ez' but it's the topic of maths i struggle the most with LOL I'M SRY. )

 

[snowflakeptical]

binomial products meaning the multiplication of 2 terms?
e.g. (x+3)(x-4) if that is the case separate them and take step by step
x(x-4)+3(x-4)
x^2 - 4x +3x -12
simplifying like terms
x^2 - x - 12

 

[teridax]

binomial products meaning the multiplication of 2 terms?
e.g. (x+3)(x-4) if that is the case separate them and take step by step
x(x-4)+3(x-4)
x^2 - 4x +3x -12
simplifying like terms
x^2 - x - 12

If you wanna save time, step two is not necessary. Just multiply the 1st constant by the 3rd constant, 2nd by 3rd, 2nd by 4th and 1st by 3rd. Immediately, you will get the third step where simplification is required.

But yeah, binomial products is the product of two binomial expressions, as a binomial itself is an expression consisting of two terms. Once you fiddle with it, it's not too difficult.

 

[snowflakeptical]

If you wanna save time, step two is not necessary. Just multiply the 1st constant by the 3rd constant, 2nd by 3rd, 2nd by 4th and 1st by 3rd. Immediately, you will get the third step where simplification is required.

But yeah, binomial products is the product of two binomial expressions, as a binomial itself is an expression consisting of two terms. Once you fiddle with it, it's not too difficult.

yeah, that step is done in my head. However, when I was in junior years and trying grasp what I was actually doing, I did that even if it was tedious

 

[BLIT2014]

http://www.mathsisfun.com/algebra/polynomials-multiplying.html


Remember to ''FOIL"

 

[notrealemily]

binomial products meaning the multiplication of 2 terms?
e.g. (x+3)(x-4) if that is the case separate them and take step by step
x(x-4)+3(x-4)
x^2 - 4x +3x -12
simplifying like terms
x^2 - x - 12

thank you!! that helped a lot more than my teacher ahaha

 

[notrealemily]

http://www.mathsisfun.com/algebra/polynomials-multiplying.html


Remember to ''FOIL"

FOIL? o.o

 

[BLIT2014]

FOIL? o.o

Check the link.

(x+3)(x-4)
First you multiply the first lot of terms,
x*x=x^2
O Then you multiple by the outer terms
x*4=4x
I Then you multiply by the inner terms
3*x=3x
L Then you multiply by the last terms
3*-4=-12

 

[Speed6]

FOIL technique, everyone should know this.

 

[BLIT2014]

http://syllabus.bos.nsw.edu.au/mathematics/mathematics-k10/content/794/


Expand binomial products by finding the areas of rectangles,
https://geogebratube.org/student/m160
https://mathspace.co/learn/world-of...al-products-i-6706/first-outer-inner-last-69/

 

[Flop21]

yeah, that step is done in my head. However, when I was in junior years and trying grasp what I was actually doing, I did that even if it was tedious

This!

We use to call it the 'CLAW'. Because it looks like a claw.

You literally just do what snowflakeptical drew every time.


___


By the way, quick tip. If you get something like (x+1)^2 you need to go ahead and write it out like (x+1)(x+1) and do what I just mentioned. You can't just square the insides.

 

[snowflakeptical]

Really foil is just the claw technique in worded explanation. Images are easier to remember

 

[Drongoski]

I just covered exactly this topic and quadratic factorisation to my new Yr-10 student an hour or two ago. It is so easy and if not learn't correctly, can become hard. I recall a student of mine (from an expensive private school) showing a technique for factorising quadratics - involving a sequence of steps (an algorithm) to ensure students get the factorisation right. The process seems to be based on the idea that you invest a few additional steps to make sure, if you follow the process correctly, you will always get it right. So the additional steps is a relatively small cost to ensure a foolproof method for factorisation.

Fascinated, I thought about it. Why all this beat-about-the-bush approach to a simple problem, easily done in 2 or 3 steps? I later referred to such elaborate factorisation methods as witchcraft! You'll be surprised how many find factorising a quadratic hard.