modifying exp.v for a different definition of poweR #91

Job	Run time
coq	45s
mathcomp-analysis-single	11m 33s
mathcomp	43s
mathcomp-classical	2m 36s
mathcomp-reals	3m 25s
mathcomp-experimental-reals	1m 49s
mathcomp-reals-stdlib	1m 25s
mathcomp-analysis	9m 27s
mathcomp-analysis-stdlib	1m 30s
ssprove	8m 53s
	42m 6s

Provide feedback