Question

solve integral (1-tan^2(x))

Answer 1

\[\int\limits_{?}^{?}1-\tan ^{2}x=\int\limits_{?}^{?}1-(\sec ^{2}x-1)\]

Answer 2

1-tan^2(x) is a nice Identity... do you know what it is ?

Answer 3

\[=\int\limits_{?}^{?}2-\sec ^{2}x\]

Answer 4

2x-tanx+C

Answer 5

just to let you know uzma, if you eliminate the _{}-{} part after "int" the limits of the integral will go away

like this

\[\int\limits\]

Answer 6

oh thanks, i dint try it :)

Answer 7

np :)

Answer 8

\[\int\limits\]

Answer 9

Lao, to remember the integrals of trig, you need to know the derivatives of them very well

Answer 10

right ?:)

Answer 11

for this one,

d/dx(tan(x)) = sec^2(x)

was the one tat uzma referred to

Answer 12

@ uzma fantastic !

Answer 13

thanks

Answer 14

another one you will see a lot is things like

\[\int\limits -\csc(x)\cot(x) dx\]

Answer 15

if you try to do u-substitution or integration by parts, it will be a tough one, but if you remember

d/dx csc(x) = -csc(x)cot(x)

then we know that the integral that I showed you will have an ans

csc(x) + C