math help
@Vocaloid
Question?
The ones you selected for 1 are correct I'm not sure if option D is an answer too because \((x^2+x)^2\) = \(x^4+2x^3+x^2\) and the leading is a 4th degree
And for #2 it is option B)
I am not sure about #3 you can ask vocaloid that
@Vocaloid
only look at the graph where x is between -2 and 3 what's the highest value the function obtains?
3?
is mehek correct on the other answers
make a tick mark where x = -2 make another tick mark where x = 3 between those two values, what's the highest y-value that the graph touches?
2
is the closest
good so 2 is your max I think Mehek is right for the other answers so far
kinda stumped on 4 tbh, let me think
i'm getting better at pre cal lol trying to solve some on my own
my pre-calc is kind of rusty, but I believe since there are 2 local maxima there are at least 2 "turns" which means a minimum degree of 3 [just considering those roots] then you would consider the complex roots (2+3i and 2 - 3i)
Mehek do you remember how do to this? ;_;
I haven't taken this :/ so nope
can y'all check these next few
am i correct and what is 5
sorry this is taking so long, but yes, your answers for 6 and 7 are right
anyway, for the intermediate value theorem, you would evaluate the function the left hand and right hand ends of the interval (for example, evaluate f(-5) and f(-4). now, treat f(-5) to f(-4) as a new interval, and if 0 is within that interval, then the original interval contains a 0
I think it's a little easier to explain with math than with English
-3,-2 one?
can you show me your work?
what did you get for f(-3) and f(-2)?
i'm graphing it honestly
you can also do it algebraically
-4,-3 appears to one too
(-3,-2) does not contain a 0 (-4,-3) does
-5,-4 -4,-3 1,2
i'm looking at the graph on mathway probably should try desmos
am i right so far?
you're missing [0,1] take a look at the graph I attached
other than that I think you're good
wolfram alpha is a very powerful mathematical software
i thought it was 0,1
I'm talking about the intervals not points
[0,1] means the interval x = 0 to x = 1 in between x = 0 and x = 1, there is one zero so [0,1] is an option
keep in mind the answer choices are intervals, not points
https://s1.postimg.org/9n9ibnzw9b/Capture.png but 0,1 is still an answer right and check 8 and help with 9?
8's good
for 9 I am not sure about formatting, but you would just find the possible roots using the p/q formula, and then test each root using synthetic division
(the rational root theorem, that is)
how would you do it if there isn't a q for example no x=3
hint: what is the coefficient on the highest powered term?
1
so x=1
x is not 1, but you would use that 1 to find the possible values of q
remember, q is all the possible factors of the coefficient on the highest powered term so what are the factors of 1?
+-2i and -1
just consider real numbers for now
the only factor of 1 is 1 so your possible values of q are +1 and -1 (or written as +- 1)
what about the constant? (4) what are the factors of 4?
2 and -2
keep going, you're missing 2 more
2i -2i
remember, we are only considering real roots for this (no i)
hint: 1 is a factor of every whole number, and if 1 is a factor of 4, what's also a factor of 4?
oh duh i'm going way ahead of myself
1,4
good so let's list out all the combinations
p = ± 4, ±2, ±1 q = ±1 so every possible combination of p/q can be tested as a root in synthetic division
so +4/-2, +1/1, etc.
so i need to divide 4/-2, 1/1 ?
yeah, you would divide all the possible combinations of p and q to find possible roots to test
so -2 and 1 ?
yes, those were two possible roots I used in the example you would need to divide ALL combinations of p and q to find ALL the roots, though. it's more than just those two
-1/1=-1
good keep going, there should be 6 possible roots
4/2=2
good
4/1=4 one more right?
good
2/1=2?
you already said this one ^^"
it's -4 to save you some time
oh oops
so our roots are +4, -4, +2, -2, +1, -1 so we can pick one root at a time to test -1 is a good choice, so perform synthetic division with x = -1 (or, x + 1 = 0)
ok lol
there shouldn't be a remainder right i get 10
that would be for +1 as a root not -1 ^^
for x = -1 the number that goes outside the synthetic division symbol is -1 I believe?
or is it 1
x=1 i just calculated
ah, so x = 1 is not a root try x = -1 as a root
awesome! so now we have x^2 +4 do you think x^2 + 4 = 0 has any more roots?
that is, does x^2 + 4 = 0 have any real number solutions? (no i)
we said -2
hint: does (-2)^2 + 4 = 0?
i just said that lol
again, does (-2)^2 + 4 equal 0?
yes
hint: (-2)^2 = (-2)*(-2) = ?
-4
try one more time
negative * negative = positive
4
good so (-2)^2+4 = 8, not 0 so -2 is not a root
oh crap duh i'm listening to an ll and doing pre cal
am done now
so do you think x^2 + 4 = 0 has any solutions?
good, it has no other solutions, so all possible roots have been found, making your problem complete
am almost done yay
10 should be right i need help with 11 mainly
I think you could do a piecewise function that excludes x = -2
and put (x-3) in the denominator to make that vertical asymptote
so for example i could say 6x^3-2x^2-x-3 for denominator?
I guess but you don't need to make it that complex
if you just put 1/(x-3) as your function it'll work fine
(it's your choice though)
anyway, after you have your function, you can write it in piecewise notation { f(x) = ______ from (-infinity,-2) { f(x) = _______ (same function) from (-2,infinity)
oh ok
so pick a function? for the numerator
actually come to think of it there's a better way
if you put (x+2) in your numerator AND the denominator this should give you a hole at x = -2
so x+2/x+2-x/3?
almost
(x+2)
(x+2)(x-3) the
is a fraction bar
whoops
(x+2) fraction bar (x+2)(x-3) should do it
how would i explain how i determined it
using the steps I have outlined above
\(\color{#0cbb34}{\text{Originally Posted by}}\) @Vocaloid if you put (x+2) in your numerator AND the denominator this should give you a hole at x = -2 \(\color{#0cbb34}{\text{End of Quote}}\)
\(\color{#0cbb34}{\text{Originally Posted by}}\) @Vocaloid and put (x-3) in the denominator to make that vertical asymptote \(\color{#0cbb34}{\text{End of Quote}}\)
is 10 right? and 12? i'm about to solve 12
yeah I think 10's good
12 is a
1 more after this to check
12 is good
13?
yes good
for 14 find the least common denominator convert both fractions to have the LCD then just add
14 i have to solve
hint: to start, try factoring both denominators then the LCD will be a bit more obvious
x x -2 x
uh I'm not sure what this means ^^
x x -4 1
try using parentheses to be more clear
x^2=(x*x) right
-2x=(-2*x)
if you have terms being added and subtracted you cannot factor each term individually, you have to consider the expression as a whole
for example, for (x^2-2x) what happens if you factor out x? make sure to keep parentheses in your answer
ypu have (x-2)
?
good, so we get (x)(x-2) as the new denominator now try factoring (x^2-4) using difference of squares
x+2 x-2
good so let's compare the left denominator and the right denominator left: (x)(x-2) right: (x+2)(x-2) how can we get them both to be the same thing?
x^+2 x-2?
uh I'm not sure what you mean by that
x*x=x^2
I think you're a little off track ^^ let me help out
left: (x)(x-2) right: (x+2)(x-2) if we multiply the "right" by x and the "left" by (x+2) what do we get?
*** note: do not distribute any parentheses yet
x^4-2x^3-4x^2+8x
please do not distribute any parentheses yet
you should have gotten: left: (x)(x-2)(x+2) right: (x+2)(x-2)(x) right?
oh ok so you wanted it exactly literally ok i'm over here trying to combine it
yeah, sorry if I wasn't clear ^_^"
piecewise function are not until next unit lol just looked for that other question it's ok
anyway, remember that, in order to keep the value of a fraction the same, you would multiply the numerator AND the denominator by the same value
so for the left-fraction, multiply the numerator and the denominator by (x+2) and then for the right fraction, multiply the numerator and the denominator by x
if you do your math correctly you should have two fractions with the same denominator then you can just add the numerators and put that over the new denominator if that makes sense
like: (A/C) + (B/C) = (A+B)/C
so multiply with the x(x-2)(x+2) we have?
let me rephrase this ^^
or by the orginal equation
your original problem is (x-4)/(x^2-2x) + (4/(x^2 - 4)) apply the multiplications to this ^
(you can use the factored form if that's easier)
x-4*(x+2)=-3x+2 x^2-2x*x+2=-x^2+2 4*x=4x x^2-4*x=x^2-4x
check your math again
your denominators should be equal
use the factored form if that's simpler
(x-4)/ [x(x-2)] + (4/[x+2][x-2]) ^ apply the multiplications to this
you should get x(x-2)(x+2) as your denominator
x+2/x^2+2? answer
mathway says the numerator is x+4?
try leaving things in factored form instead of expanding things out
at the very end, you can do the expansions
I wouldn't trust mathway, their software isn't good for calculations
also can we open a new question? this one is lagging a lot
I can transfer my work over
so x+2 for numerator is correct and sure
I don't think x + 2 is the correct numerator
im confused
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