Missing function on HP 42S

[lrdheat]

I used to think that the lack of an Nroot key on the HP 42S was a bit of a shortcoming, especially if one wanted to integrate an equation that had fractional powers involved where negative numbers were involved. It would be a convenience to have such a key on the HP 42S, but it is not a hard work around…it is easy to break such an integral into 2 integrals. In the case of the negative part of the integral’s domain in an odd numbered root, to make that part of the integral produce a negative number, integrate it from the absolute value of the lower end of the domain as lower limit, and use 0 as the upper limit. Store the result. The domain from 0 on up can be integrated in normal fashion. This can then be added to the stored result for the answer to the full domain integral.

Carry on…