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help_with_math
 4 years ago
Integration help!
integral of sec^5 x dx
help_with_math
 4 years ago
Integration help! integral of sec^5 x dx

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Walleye
 4 years ago
Best ResponseYou've already chosen the best response.1/barf im guessing u sub will help you here

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0yes integration by parts

across
 4 years ago
Best ResponseYou've already chosen the best response.1I read it as sec^5(x)x for a moment there. Hmm, in this case, you have to use a reduction formula.

Walleye
 4 years ago
Best ResponseYou've already chosen the best response.1red formula will work if you have it

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0well i havent learned taht so is tehre anoterh way to do it by parts

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1( 1 + tan ^2 x ) ( 1 + tan^2 x ) (sec x )

across
 4 years ago
Best ResponseYou've already chosen the best response.1I had to look it up\[\frac{\sin(x)\sec^{m1}(x)}{m1}+\frac{m+2}{m1}\int\sec^{m2}(x)dx\]

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0this is wat i have so far: \[\int\limits_{}^{}\sec^3 x (\sec^2 dx)\] \[\int\limits_{}^{}\sec^3 x (1+\tan^2 x dx)\] \[\int\limits_{}^{}(\sec^3 x +\sec^3 x \tan^2 x )dx\]

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1so do a u sub with u = tan x , du = sec^2 x dx

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0\[\int\limits_{}^{}(\sec^3 x) + \int\limits_{}^{}(\sec^3 x \tan^2 x) dx\] can i use u sub after this step

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1you will prolly end up with a ( 1 + u ) ^(to some power ) then it a simple integration

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0can u show me the steps after the one i just did

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0ughh i hate problems liek this!! XD...requires too much work

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1yea, it may have to be broken up into parts I cant get rid of one of the sec^x check out: http://www.wolframalpha.com/input/?i=integrate+sec^5+x

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1this IS a reduction formula for powers of sec.

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0i did n idont understand it b.c it uses smthng i didnt leard which is teh reduction formula thing

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0then again do u mind tellin me wat that is

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0or how to use it

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1yea, your instructor may not accept a reduction formula answer, it the quick way, but there is a trigonometric solution for this.

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0cool i will prob understand that if u explain

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0the trig solution i mean

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1there is an identity that will lead to an integral of u. anywa here is a like with the reduction formula for secant, and others http://www.sosmath.com/calculus/integration/moretrigpower/moretrigpower.html

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1as a matter of fact I bet your textbook has a table of integrals for integrals of powers of secant

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0what is the dffnce between sex^n (x) and sec^n (ax)

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0i wud use the first formula right? sec^5 (x) = sec ^52 (x) sec^2(x) = sec^3 (tan^2 x * sec^2 x 1)

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0where do u go on from there

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0omg i havent done definite integrals!

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1∫sec^5dx=1/4sec^3xtanx+3/4∫sec^3xdx

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1no definite integrals here

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0hmm how did u get 1/4 sec ...etc

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1then apply the reduction formula ( or integrate ) \[\int\limits \sec ^ 3 x dx\]

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0im confused how u got the previous step thou

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1its from the reduction formula, it ends with an integral of ∫sec^3xdx

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0i mean teh 1/4 sec part im confused about

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1in the reduction formula it 1/(a(n1) n=5, the power of secant a = 1

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0ok so now how did u get 3/4?

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1from the reduction formula: (n2)/(n1) again n = 5, the power of the secant

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1you instructor will be either impressed or put off that you are using the integral tables. :)

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0lol...he will b impressed hopefully...i have a test 2mm n im trying to udnerstand probs idk

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1yea the trigonometric integrals take practice( obviously )

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0srry this is new to me so after taht step wat do u do..u still have a integral of sec^3 dx to deal with

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1right! so integrate the sec^x or use the formula again, but this time with n = 3, see?

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1sec^x is short, but it indefinite integral has many parts.

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0so after using n=3 do u get 1/2 sec x dx

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1right ( n2)/(n1) this time the formula will end with \[\int\limits \sec x dx\]

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0wait but isnt is half secant

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0so how is teh integral jsut sec

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1no the formula will end ith ∫secxdx, integrate that and you are done.

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1\[\int\limits \sec x dx = \ln ( \sec x +tanx ) + C\]

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0so teh final answer is: 1/4 sec^3 x tanx + 3/4 ...idk teh rest

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.11/4 sec^3 x tanx + 3/4∫sec^3xdx then apply the formula again for ∫sec^3xdx that answer will end with ∫sec xdx integrate ∫secxdx, done!

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0so the final asnwer is: 1/4 sec^3 x tanx + 3/8 sec x tanx + tn (secx+tanx) + C

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0SRY TAHTS SUPPOOSED TO be ln not tn

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1right, distribute the 3/4, I didnt work it all out but it looks right. Those tables are in you textbook right, in the appendix?

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0let me check now

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0under wat heading shud i looj for te hreduction formulas

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0i see basic forms, forms invlving sqrt of (a^2+u^2, forms involving (a^2  u^2), forms involvung sqrt of (u^2  a^2), forms involving a+bu, trig forms, inverse trig forms, exp and log forms, hyperbolic forms

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1Tables of integrals, Lists of Integrals usually in the appendix, could be on the inside covers.

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0yeah i see them in the appenxix...jsut under wat heading of integrals will i fimd teh reduction formulas

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0or wher u jsut letting me know taht tehre was a table of integrtals

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1that really what we were using, an integration formula, so you can integrate by parts or look up the formula.

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1there might be one for ∫sec^n (ax)dx

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1might not http://integraltable.com/

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0ths is wat is in my bk...sec^n du = 1/n tan u sec^n2 + (n2/n1) *integral of sec^n2 u du

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0i guess tahts anoterh form of te one u showed me

Roachie
 4 years ago
Best ResponseYou've already chosen the best response.1right that one dont account for a coefficient on x. so, yea, you seem to have it. Im out. ( gotta brush up on my integrals ;) )

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0THANK U SOOOOO MUCH!!! PLUS THE WEBSITE LOOKS SUPER HELPFUL =)

help_with_math
 4 years ago
Best ResponseYou've already chosen the best response.0ii imma go study sum more
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