how to combine:
(x+2) (x-2)
difference of squares
multiply xs and the 2s
X x X then X x -2 then 2xX then 2 x -2
\(\Large\color{black}{ \displaystyle ({\rm \color{blue}{b}}-{\rm \color{red}{a}})({\rm \color{blue}{b}}+{\rm \color{red}{a}})=}\) \(\Large\color{black}{ \displaystyle {\rm \color{blue}{b}}({\rm \color{blue}{b}}+{\rm \color{red}{a}})- {\rm \color{red}{a}}({\rm \color{blue}{b}}+{\rm \color{red}{a}})=}\) \(\Large\color{black}{ \displaystyle {\rm \color{blue}{b}}^2+{\rm \color{red}{a}}{\rm \color{blue}{b}}- {\rm \color{red}{a}}{\rm \color{blue}{b}}-{\rm \color{red}{a}}^2=}\) \(\Large\color{black}{ \displaystyle {\rm \color{blue}{b}}^2\cancel{+{\rm \color{red}{a}}{\rm \color{blue}{b}}}\cancel{- {\rm \color{red}{a}}{\rm \color{blue}{b}}}-{\rm \color{red}{a}}^2=}\) \(\Large\color{black}{ \displaystyle {\rm \color{blue}{b}}^2-{\rm \color{red}{a}}^2.}\)
so, see how the middle term cancels?
And this is for any "a" and "b" values. The middle term always cancels.
making it \[x ^{2} -?\]
well, we just now proved that \(\Large\color{black}{ \displaystyle ({\rm \color{blue}{b}}-{\rm \color{red}{a}})({\rm \color{blue}{b}}+{\rm \color{red}{a}})= {\rm \color{blue}{b}}^2-{\rm \color{red}{a}}^2}\)
right
\(\Large\color{black}{ \displaystyle ({\rm \color{blue}{x}}-{\rm \color{red}{2}})({\rm \color{blue}{x}}+{\rm \color{red}{2}})=??}\)
just compare the form
x^2 is right, and minus what ?
2
yes, so x^2-2^2
which is same as what? how can you simplify 2^2 ?
-4
yes, x^2-4
I can't really see the attachment. sorry
try zooming in plz
go to the view tab in that doc.
I think I see it
\(\large\color{black}{ \displaystyle \frac{3 }{8x^3y^3} -\frac{1 }{4xy} }\) \(\large\color{gray}{ \displaystyle a.~~~~~\frac{x^2y^2-3}{4x^3y^3} }\) \(\large\color{gray}{ \displaystyle b.~~~~~\frac{2x^2y^2-3}{8x^3y^3} }\) \(\large\color{gray}{ \displaystyle c.~~~~~\frac{2}{8x^3y^3} }\) \(\large\color{gray}{ \displaystyle d.~~~~~\frac{3-x^2y^2}{4x^3y^3} }\)
am I right ?
yes
okay, multiply top and bottom of the second fraction by BLANK. this BLANK has to be making the denominator of the 2nd fraction [into] the same thing as the denominator of the 1st fraction \(\large\color{black}{ \displaystyle ( }\) i.e. [into] \(\large\color{black}{ \displaystyle 8x^3y^3 }\) in the denominator \(\large\color{black}{ \displaystyle ) }\).
right thats what i got
what did you get ?
\[\frac{ 3 }{ 8x ^{3} y ^{3}} - \frac{ 1 }{ 4xy }\]
oh, OPTION D, correction. \(\large\color{red}{ \displaystyle \frac{3 -2x^2y^2}{8x^3y^3} }\)
how would you make the common denominator ?
\(\large\color{black}{ \displaystyle \frac{3 }{8x^3y^3} -\frac{1 \color{red}{\times 4x^2y^2}}{4xy\color{red}{\times 4x^2y^2}} }\) am I correct, or am I making a little mistake ?
Your right!
no I am not... are you sure?
with this multiplication, do I get the common denominator ?
why are you timing 4*4
to get you to correct me, lol
8-8 =0
so, what should I multiply on top and bottom of the 2nd fraction then ?
im thinking 1 so that way 1*4=4 then 8=4 equals 4... but then that wouldnt be right considering we need 8 so probbaly 4*1
or is that wrong?
Im going with 1
\(\large\color{black}{ \displaystyle \frac{3 }{8x^3y^3} -\frac{1 \color{red}{\times \color{blue}{2}x^2y^2}}{4xy\color{red}{\times \color{blue}{2}x^2y^2}} }\)
that would make it a common denominator, wouldn't it ?
can you finish simplifying this fraction?
im trying
so im going with D considering i got 3in the numerator and 8 in the denomenator
actually if iwent 3-2 that would be 1 so it could be A
yeah so on top of that i'd also get 4 in the bottom so its A for sure
@pitamar
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