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  • Quantum Theory Integrals and Techniques

Quantum Theory Integrals and Techniques

Table of Useful Integrals, etc. xe- 2 a 2a XP ;xe_3xJ 2a2 4a a -1 3 5(2n-)1 r 2a+1an n! 2an+1 x"e~ax dx =_n! an+1 Integration by Parts: fUdV = UV (VdUU and V are functions of x. Integrate from x = a to x = b Ssin(ax) dx = - cos(a) a 2 4a 8 16a 4a where a2 b2 2(a+b 2(a-1 2(a+1) 2(a-) 2(a+1) (xsin(ax) dx=_xsin(2a) cos(2a) 4 4a 8a2 cos(2ax =x 1 4a 8a3 sih 2a 4a cos (a+bx xsin (a-xxsin (a+ x 2a+) 2(a-b 2(a+b xsin(ax sin(b} dx 2(a- sin(ax) xcos(a) sin(ax dx= xsin(ax.cos(ax sin(ax) os(ax) dx (ax)dx=+sin(2ay) 2 4a 4a Taylor Series: Geometric Series: Euler's Formula: e =coso+isin Quadratic Equation and other higher order polynomials: ax2+bx+c=0 -bb2 - 4ac X 2a ax4+bx2+c=0 -b vb2 -4ac x=+ 2a General Solution for a Second Order Homogeneous Differential Equation with Constant Coefficients: If: y'+ py+qy=0 Assume a solution for y: y=esxy=sesxy=s2esx s2esx + psesx +qesx =0 O=b+sd+zs pue Hencey=c,e+c,e2 Conversions from spherical polar coordinates into Cartesian coordinates: x =rsin0cos y =rsinsin x=rcos0 dv = r2 sin0 drdO do oo>I>0 I>0>0 1Z>