#evaluate if m is natural
1 messages · Page 1 of 1 (latest)
let
$\int(\sqrt[m]{(k^{3m}+k^{2m}+k^m)(2k^2+3k+6)})dx$
let
Agh I'm too lazy to multiply that
yeah
hmm how?
mhm
Yes I did
That's why you have $k^{3m}+k^{2m}+k^m$
let
I've defined k as $x^m$
let
let
So when you get $x^{3m}$ inside the root it becomes $(x^{3m})^m$
let
So that's basically $(x^m)^{3m}$
let
let
So that's what I did here
You simplify this
and then the idea is that you can effectively remove the root
You won't need substitution
One sec, I'll remove the root
Yes, but when we remove the root you'll get x
I'm too lazy to simplify it so let me get wolfram
see, doing that by hand is pain
just...pain
Basically, we know k=x^m
so
If you're taking the mth root of this you're effectively removing that exponent
So you can just replace k with x
Mhm
basically, $\sqrt[m]{k^{m+1}}=\sqrt[m]{x^{m(m+1)}}$
let
m and m cancel each other
you get x^m+1
Basically, we have replaced k with x by taking the root
sure
Right
Sorry, went offline
Let's do this step-by-step
$3k^{m+1}+2k^{m+2}+3k^{2m+1}+2k^{2m+2}+3k^{3m+1}+2k^{3m+2}+6k^{3m}+6k^{2m}+6k^m$
let
now
let's substitute k with its definition
x^m
$3(x^m)^{m+1}+2(x^m)^{m+2}+3(x^m)^{2m+1}+2(x^m)^{2m+2}+3(x^m)^{3m+1}+2(x^m)^{3m+2}+6(x^m)^{3m}+6(x^m)^{2m}+6(x^m)^m$
let
yeah?
Now, using the laws of exponents, we can multiply the exponents in each term
or
Let's take x^m as the common term
nvm
$3x^{m(m+1)}+2x^{m(m+2)}+3x^{m(2m+1)}+2x^{m(2m+2)}+3x^{m(3m+1)}+2x^{m(3m+2)}+6x^{m(3m)}+6x^{m(2m)}+6x^{m(m)}$
let
Yeah?
we've just multiplied the exponents
Pretty much, yea
Except, I've combined m with the other exponents
basically $(x^k)^m=x^{km}$
let
Let's take the mth root of this
wait..
Ah it's addition
You can't really distribute it like that
yeah, took me a while
I suppose you can sub it with dk
well, if n is natural x^m should be differentiable, right?
Well if you wanna know
let
let
So did you get t?
Ah fair enough
Damn, I can't believe I didn't see that
not seeing these steps is gonna kill my math skills
But yeah, tons of practice is required
$\frac{sin^6x + cos^6x}{sin^2x+cos^2x}$?
let
Ah right
meckron
$(sin^4x+sin^2xcos^2x+cos^4x)(\frac{1}{sin^2x}+\frac{1}{cos^2x})
= (sin^2x+cos^2x+cot^2xsin^2x)+(cos^2x+sin^2x+tan^2xcos^2x)$
let
Without subbing?
oh that's gonna kill me
sorry, never took an integrals course
yet
$\frac{1-3sin^2xcos^2x}{sin^2xcos^2x}=\frac{1}{sin^2xcos^2x}-3\ \int{k} = \int{sec^2xcsc^2x}dx - 3x = tanx+cotx-3x+C$
let