_______ _______ _______ \/ x + 5 + \/ x - 3 > \/ x + 7
sqrt(x - 3) + sqrt(x + 5) > sqrt(x + 7)
/ ____ \ | 4*\/ 21 | And|x < oo, -3 + -------- < x| \ 3 /
(x < oo)∧(-3 + 4*sqrt(21)/3 < x)
____ 4*\/ 21 (-3 + --------, oo) 3
x in Interval.open(-3 + 4*sqrt(21)/3, oo)