How do i simplify radical expressions?
what radical question
the square root of 125n
you do 125/6 then 9*9
\[\large \sqrt{125n}\] Hint \[\large 125 = 25 \times 5\]
So we might really have \[\large \sqrt{25 \times 5 \times n}\]
n=5 you twat
so the answer would be...?
5 babe dont listen to them
so the n doesnt matter? @jeedeee
\[\large \sqrt{25 \times 5 \times n}\] the square root of 25 is 5 so we have \[\large 5\sqrt{5n}\]
so thats the answer? hah
the answer is 2.5 n=2.5
yeah @Mychelynn99 Idk where @jeedeee was looking...all you asked was to simplify √125n Idk where the 6 or 9*9 came from?
sooooo the answer is 5n?
The answer would be \[\large 5\sqrt{5n}\]
Okay thanks!
So we have \[\large \sqrt{512k^2}\] We know that \[\large 512 = 256 \times 2\] so we really have \[\large \sqrt{256 \times 2 \times k^2}\] we know that the square root of 256 = 16 so we have \[\large 16\sqrt{2 \times k^2}\] and we also know that \[\large \sqrt{k^2} = k\] so alltogether we have \[\large 16k\sqrt{2}\]
@Mychelynn99 :)
so if i have the square root of 80p^3 the answer would be.... umm yeah i still dont fully understand @johnweldon1993
Alright no problem Alright so notice how first...I take the number (80 here) and break it up We know: 40 times 2 = 80 20 times 4 = 80 16 times 5 = 80 <--- right here is where we stop Why? because we know 16 is a perfect square...
Perfect square meaning 1^2 = 1 2^2 = 4 3^2 = 9 4^4 = 16 <--- look at that
So how does that help? Well...if we know that 80 can be broken up into 16 times 5....we can write it as \[\large \sqrt{16 \times 5 \times p^3}\]
And as we just found out....the square root of 16...is 4....since 4 squared.. 16 \[\huge \sqrt[2]{4^2} = 4\]
So now what we have....knowing that the square root of 16...is 4....is \[\large 4\sqrt{5p^3}\]
Making sense so far hun?
kinda...
Which part is confusing? :)
how to know to stop at 16 times 5
Oh okay.... alright firstly....we need to understand perfect squares... meaning when you square a number....(multiply it by itself) what does it equal? so for example when you square 1....(multiply 1 by itself) so \[\large 1 \times 1 = 1\] so \[\large 1^2 = 1\] does that make sense?
yes
Great.... so if we continue on that path 2 squared would be \[\large 2^2 = 2 \times 2 = 4\] \[\large 3^2 = 3 \times 3 = 9\] \[\large 4^2 = 4 \times 4 = 16\] okay?
Got it
Alright...so back to the original problem lets ignore the p^3 for this part... imagine we just have \[\large \sqrt{80}\] Like we said...we want to figure out if any perfect squares divide evenly into 80
40 times 2?
We do that...because the square root....of a number squared....is the number for example... \[\large \sqrt{1^2} = 1\] \[\large \sqrt{5^2} = 5\] etc...the SQUARE root and the SQUARE cancel out..leaving us with just the number
So yes...lets list what goes into 80 evenly If we multiply 40 times 2...we get 80.....but is either 40 or 2 a perfect square? Nope...so we keep going... if we multiply 20 times 4....we get 80....now we see that 4 is indeed a perfect square \(\large 2^2 = 4\) so we CAN do that...but...we see that 20 can still be broken down a bit so we can keep going... (we CAN stop there though....but we wont :)
So lets continue now... we know that 16 times 5 = 80 ....and we want to stop here.....because we know that 16 is a perfect square \(\large 4^2 = 16\) and we can see that 5 cannot be broken down anymore...
got it so far
Great....so lets start from the beginning.. \[\large \sqrt{80p^3}\] Now that we know 80 can be written as 16 times 5...lets write it as so... \[\large \sqrt{16 \times 5 \times p^3}\]
We just found...that 16...is a perfect square....it is \(\large 4^2 = 16\) since that is the case...we can write the 4 on the outside \[\large 4\sqrt{5p^3}\] still good?
yupp
Great....now we focus on the \(\large p^3\) We know that \[\large p^3 = p^2 \times p\] right?
right
So lets write that \[\large 4\sqrt{5 \times p^2 \times p}\] okay?
Remember how the square root of a squared number...is just the number? \[\large \sqrt[2]{7^2} = 7\] and \[\large \sqrt[2]{9^2} = 9\] well the same rule stands here...just imagine 'p' was a number...so \[\large \sqrt[2]{p^2} = p\] make sense?
clear as day
Great! So just like when we wrote the 4 on the outside when we simplified \(\large \sqrt[2]{16}\) we can now write 'p' on the outside since we simplified that p^2 so altogether we have \[\large 4p\sqrt{5p}\]
And that would be our final answer there :)
ugh this is so complicated!
What confused you there hun?
why is there a p by the 5 too?
Well remember we had \[\large 4\sqrt{5 \times p^3}\] and we knew that \[\large p^3 = p^2 \times p\] so when we wrote tht in...we had \[\large 4\sqrt{5 \times p^2 \times p}\]
So when we simplified \(\large \sqrt{p^2}\) we do indeed get the 'p' that showed up outside the square root...but notice how we never touched that last 'p' that stays inside the square root \[\large 4p\sqrt{5p}\]
gotcha
sorry imm askng so much
No not at all hun :) I want to make sure you get this :)
So..can you help me on another?
Of course :)
the square root of 45p^2
Alright...so same thing here... what times what = 45? list anything you can think of...
7*5
but thats not a perfect square
\[\large 7 \times 5 \cancel{=}45\]
LMAO blonde moment 9*5
Haha we all have em ;P Okay....good :) ....now...does that have a perfect square?
nope
.....sure? ... :) hint* \[\large 3^2 = ?\]
ohh 3*3=9
Mmhmm :) so we know that 9 is a perfect square :) \[\large \sqrt{45p^2}\] we found that 45 can be written as 9 times 5 so \[\large \sqrt{9 \times 5 \times p^2}\] And we just saw that 9 is \(\large 3^2\) so we write that 3 on the outside like before... \[\large 3\sqrt{5p^2}\] making sense?
makes sense. I think im finally catching on. omg but how would i do square root of 28x^3y^3
Focus on 1 part at a time :) the 28 part...what times what = 28?
7 times 4
so it would be 7*4*x^3*y^3?
RIGHT :) so we have that \[\large \sqrt{7 \times 4 \times x^3 \times y^3}\] wheres the perfect square?
4 2*2
Right! :D good you are getting it :D so write that 2 on the outside... \[\large 2\sqrt{7 \times x^3 \times y^3}\] remember before...how we knew that \(\large p^3 = p^2 \times p\) ?
im kinda lost
Where hun?
the p hah
lol I was just bringing up that last problem... where we had \[\large p^3\] and we knew we can write that as \[\large p^2 \times p\]
oh yeah haha
Alright lol so here we have that same thing...but we have \[\large x^3\] and \[\large y^3\] so those can be written as ?
so x^2*x?
Mmhmm...anddddddd (the 'y' one now :)
y^2*y
Great! Alltogether we have \[\large 2\sqrt{7 \times x^2 \times x \times y^2 \times y}\] right?
Right
Now remember what happened last time? \[\large \sqrt[2]{p^2} = p\] sooo here when we simplify both the x^2 and the y^2...we get?
umm not sure
well it would be the same thing that happened before....I was bringing that 'p' there again to show what happened... since we knew that √p^2 became p we know that √x^2 will be x and that √y^2 will be y right?
oh psh duh okay so x^2 would be x, right? and same with y
Mmhmm..so lets catch up...we had \[\large 2\sqrt{7 \times x^2 \times x \times y^2 \times y}\] and now we know...when we simplify the x^2 and the y^2...we will have an 'x' and a 'y' on the outside again....but remember...we never touch the other x and the other y that are in there... so alltogether we have \[\large 2xy \sqrt{7xy}\]
alrighty
But...does that make sense?
yes
Awesome :)
Feel free to message me if you need any more help :)
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