Math formulas and cheat sheets for Definite integrals of trig functions

Definite integrals of trig functions

Note: In the following formulas all letters are positive.

Basic formulas

∫π/20sin2xdx=∫π/20cos2xdx=π4
∫∞0sin(px)xdx=⎧⎩⎨⎪⎪π/2 0−π/2p>0p=0p<0
∫∞0sin2pxx2=πp2
∫∞01−cos(px)x2dx=πp2
∫∞0cos(px)−cos(qx)xdx=lnqp
∫∞0cos(px)−cos(qx)x2dx=π(q−p)2
∫2π0dxa+bsinx=2πa2−b2−−−−−−√
∫2π0dxa+bcos(x)=2πa2−b2−−−−−−√
∫∞0sinax2dx=∫∞0cos(ax2)dx=12π2a−−−√
∫∞0sinxx√dx=∫∞0cosxx√dx=π2−−√
∫∞0sin3xx3dx=3π8
∫∞0sin4xx4dx=π3
∫∞0tanxxdx=π2
∫π/20dxa+bcosx=arccos(b/a)a2−b2−−−−−−√

Advanced formulas

∫π0sin(mx)⋅sin(nx)dx={0π/2m,n integers and m≠nm,n integers and m=n
∫π0cos(mx)⋅cos(nx)dx={0π/2m,n integers and m≠nm,n integers and m=n
∫π0sin(mx)⋅cos(nx)dx={02m/(m2−n2)m,n integers and m+n oddm,n integers and m+n even
∫π/20sin2mxdx=∫π/20cos2mxdx=1⋅3⋅5…2m−12⋅4⋅6…2mπ2
∫π/20sin2m+1xdx=∫π/20cos2m+1xdx=2⋅4⋅6…2m1⋅3⋅5…2m+1
∫π0sin2p−1xcos2q−1xdx=Γ(p)Γq2Γ(p+q)
∫∞0sin(px)⋅cos(qx)xdx=⎧⎩⎨⎪⎪ 0π/2π/4p>q>00<p<qp=q>0
∫∞0sin(px)⋅sin(qx)x2dx={πp/2πq/20<p≤qp≥q>0
∫∞0cos(mx)x2+a2dx=π2ae−ma
∫∞0xsin(mx)x2+a2dx=π2e−ma
∫∞0sin(mx)x(x2+a2)dx=π2a2(1−e−ma)
∫2π0dx(a+bsinx)2=∫2π0dx(a+bcosx)2=2πa(a2−b2)3/2
∫2π0dx1−2acosx+a2=2π1−a2,  0<a<1
∫π0xsinxdx1−2acosx+a2=⎧⎩⎨⎪⎪⎪⎪πaln(1+a)πln(1+1a)|a|<1|a|>1
∫π0cos(mx)dx1−2acosx+a2=πam1−a2,  a2<1
∫∞0sin(axn)dx=1na1/nΓ(1/n)sinπ2n,  n>1
∫∞0cos(axn)dx=1na1/nΓ(1/n)cosπ2n,  n>1
∫∞0sinxxpdx=π2Γ(p)sin(pπ/2),  0<p<1
∫∞0cosxxpdx=π2Γ(p)cos(pπ/2),  0<p<1
∫∞0sin(ax2)cos(2bx)dx=12π2a−−−√(cosb2a−sinb2a)
∫∞0cos(ax2)cos(2bx)dx=12π2a−−−√(cosb2a+sinb2a)
∫∞0dx1+tanmxdx=π4