Let x be a positive real number. (a) Suppose that m, n, p, q are integers (with n and q nonzero) such that m/n = p/q. Show that (xm)/n = (x) /q. (b) Explain briefly why the result of part (a) allows us to define x for a Q as x = (xm)1/n, where m and n0 are integers such that a = = m/n. (c) Show that x+b xx and xab = (xa)b for any a, a,b Q.