How to bring plus or minus the error to the degree?

Question

Mathematics

Good afternoon, there are a lot of problems that need to be solved, but I don’t know how ..
Namely, you need to bring the error to a degree or multiply one error by another.
a) The length of the edge of the cube a = (38.0 ± 0.3) cm. Calculate its volume V. Relationship formula: V = a^3
b) U = 120.50 ± 0.23; I=5.240±0.0052. Relationship formula: P = UІ
How to find these P and V, thanks for any help)

Answer 1

I don’t know where you got the expression “bring to a power”, but everything is solved very simply: you must first calculate the results without taking into account the error, then calculate what the initial values ​​will be, taking into account the error (for example, the minimum cube length is 37.7 and the maximum - 38.3), calculate the results using these extreme values, and then subtract the "ideal" result from them to get the error values ​​of the final value.

Answer 2

See the solution for multiplying two numbers , three - in the same way