1
ARKA(REEK)
·2010-07-20 03:49:55
Take cos2x common from the bracket term in the denominator ... and also from numerator .... cancel the cosine terms.
The expr. stands ... ∫(5tan x + 6)(2sin 2x + 3 cos2x)√(tan2x + 4)dx
Then take cos2x common from the other term in denominator and put it in numerator as sec2x.
The expr. now is: ∫(5tan x + 6)sec2x(2tan2x + 3)√(tan2x + 4)dx
Take tan x = z
sec2x dx = dz
The expr. stands:
∫(5z+6) dz(2z2+3)√(z2+4)
Then break the expr. into:
5∫z dz(2z2+3)√(z2+4) + 6∫dz(2z2+3)√(z2+4)
Now the expr. can be easily evaluated ....
1
जय
·2010-07-20 04:33:34
aaha ..........................
explain fully upto last anser..........
1
ARKA(REEK)
·2010-07-20 05:22:04
I just figured out that the 2nd part is going to give u a little bit of problem but the first part is easy as hell!!!
In first part take (z2+4) = t2
∫t dt(2t2-5) - 6/5 * ∫2(z2+4) - (2z2+3) (2z2+3)√(z2+4)dz
now I'm sure u can do the first part.
The only trouble lies in the second part ....
2nd part: -12/5 * ∫√(z2+4)
(2z2+3)dz + 6/5 * ∫dz√(z2+4)dz
Now The expr. is: -12/5 * ∫√(z2+4)(2z2+3)dz + 3/5 * tan-1 z/2
Please give me some time .... I will try to come up with a simplified solution to the 2nd part.
1
जय
·2010-07-20 08:00:48
ok..............take ur time...............
62
Lokesh Verma
·2010-07-20 10:30:59
i guess there is a better way..
break into two parts.. one having sin in the numerator and another with cos in numerator..
Now in the part where the numerator is sin take the denominator only in cos and then substitute cos x =t... and vice versa..
now can you figure the solution?
1
ARKA(REEK)
·2010-07-20 20:54:40
I just figured out the second part ... it could be done in a better way.
2nd part:
6∫dzz3(2+3z-2)√(1+4z-2)
Now take 1+4z-2 = t2
The expr. now is: -6/4 * ∫t dt(3t2+5)4t
=-6∫dt(3t2+5)
Now I'm am sure that u have enough knowledge and intellect to calculate this part ..... hope there are no calculation mistakes...