Begin2.DVI

(Ben Green) #1





eaxsinbx dx=

(
asinbx−bcosbx
a^2 +b^2

)
eax+C






eaxcosbx dx=

(
acosbx+bsinbx
a^2 +b^2

)
eax+C






eaxsinnbx dx=

(asinbx−nbcosbx
a^2 +n^2 b^2

)
eaxsinn−^1 bx+n(n−1)b

2
a^2 +n^2 b^2


eaxsinn−^2 bx dx






eaxcosnbx dx=

(acosbx+nbsinbx
a^2 +n^2 b^2

)
eaxcosn−^1 bx+n(n−1)b

2
a^2 +n^2 b^2


eaxcosn−^2 bx dx

Another way to express the above integrals is to define

Cn=


eaxcosnbx dxandSn=


eaxsinnbx dx, then one can write the reduction formulas

Cn=acosabx (^2) ++nnb (^2) b 2 sinbxeaxcosn−^1 bx+n(n−1)b
2
a^2 +n^2 b^2 Cn−^2
Sn=asinabx (^2) +−nnb (^2) bcos 2 bxeaxsinn−^1 bx+n(n−1)b
2
a^2 +n^2 b^2 Sn−^2
558.

xeaxsinbx dx=
([2ab−b(a (^2) +b (^2) )x] cosbx+ [a(a (^2) +b (^2) )x−a (^2) +b (^2) ] sinbx
(a^2 +b^2 )^2
)
eax+C
559.

xeaxcosbx dx=
([a(a (^2) +b (^2) )x−a (^2) +b (^2) ] cosbx+ [b(a (^2) +b (^2) )x− 2 ab] sinbx
(a^2 +b^2 )^2
)
eax+C
560.

eaxlnx dx=a^1 eaxlnx−a^1
∫ 1
xe
axdx
561.

eaxsinhbx dx=
[asinhbx−bcoshbx
(a−b)(a+b)
]
eax+C, a 6 =b
562.

eaxsinhax dx= 41 ae^2 ax−x 2 +C
563.

eaxcoshbx dx=
[acoshbx−bsinhbx
(a−b)(a+b)
]
eax+C, a 6 =b
564.

eaxcoshax dx= 41 ae^2 ax+x 2 +C
565.
∫ dx
α+βeax=
x
α−
1
aαln|α+βe
ax|+C
566.
∫ dx
(α+βeax)^2 =
x
α^2 +
1
aα(α+βeax)−
1
aα^2 ln|α+βe
ax|+C
567.
∫ dx
αeax+βe−ax=





1
a

αβ
tan−^1
(√α
βe
ax
)
+C, αβ > 0
1
2 a

−αβln
∣∣
∣∣

eax−

−β/α
eax+

−β/α
∣∣
∣∣
∣+C, αβ <^0
Appendix C

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