Formula for average value using integration isn't, financial maths formula to calculate interest rates for months isn't eg (1+r)^12 = 1+i where r is monthly interest and i is APR/AER. Calculating the modulus of a complex number isn't. The equation of a tangent to a circle x^2+y^2=r^2. There are some formula in the log tables that you just change the sign for and it gives you another formula like the internal and external divisor and the compound interest formula become reducing balance depreciation when you change the sign.

c.ohaolain—