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wendo
 3 years ago
1. integral sin x/(cos x )^2= ?
2. integral (23t)^6 dt=?
wendo
 3 years ago
1. integral sin x/(cos x )^2= ? 2. integral (23t)^6 dt=?

This Question is Closed

dpaInc
 3 years ago
Best ResponseYou've already chosen the best response.3for the first one, u=cosx

lgbasallote
 3 years ago
Best ResponseYou've already chosen the best response.0this doesnt seem like a usub problem @dpaInc looks like that basic application of general power formula

Romero
 3 years ago
Best ResponseYou've already chosen the best response.0@lgbasallote Not for the first one

dpaInc
 3 years ago
Best ResponseYou've already chosen the best response.3not necessarily but i like to do it so I don't miss the derivative of 23t...

lgbasallote
 3 years ago
Best ResponseYou've already chosen the best response.0me too...that formula is too confusing :/ kinda like doing limits to find derivative

dpaInc
 3 years ago
Best ResponseYou've already chosen the best response.3and @Romero , yes there's more than one way to skin this cat.. for the first one, the integrand can be rewritten as secxtanx

wendo
 3 years ago
Best ResponseYou've already chosen the best response.0from my caculation first one is 1/cosx+c second one is (23t)^7/21 +c is that right

lgbasallote
 3 years ago
Best ResponseYou've already chosen the best response.0i think there should be a negative on #1

campbell_st
 3 years ago
Best ResponseYou've already chosen the best response.0looks like a nice simple substitution to me... but I'm still waiting for the rooster eggs to roll off the roof

lgbasallote
 3 years ago
Best ResponseYou've already chosen the best response.0#2 seems right though @campbell_st whatis it with you and eggs :p

Romero
 3 years ago
Best ResponseYou've already chosen the best response.0Second one is right. You just wrote it weird so it looks like the ^7 is getting divided by 21

Romero
 3 years ago
Best ResponseYou've already chosen the best response.0derivative of cos will give you a negative so when you do the chain rule you will need to cancel that negative with another one.

quarkine
 3 years ago
Best ResponseYou've already chosen the best response.0these are too basic...perhaps u need to revisit the integration methods... 1/cosx and ((23t)^7)/(3*7)

freckles
 3 years ago
Best ResponseYou've already chosen the best response.1\[\int\limits_{}^{}\frac{\sin(x)}{(\cos(x))^2} dx ...u=\cos(x) =>du=\sin(x) dx ......\int\limits_{}^{}\frac{du}{u^2}=\int\limits_{}^{}u^{2} du\] \[\int\limits_{}^{}(23t)^6 dt....u=23t=> du=3 dt .....\int\limits_{}^{}u^6 \frac{du}{3}\]

.Sam.
 3 years ago
Best ResponseYou've already chosen the best response.0#2 \[\int\limits (23 t)^6 \, dt\] u==23t, du=3dt \[\frac{1}{3}\int\limits u^6 \, du\] \[\frac{u^7}{21}+c\] \[\frac{(23 t)^7}{21} +c\]
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