2/ 10 pts ] Show that 4x2 + 7x log (x)-1 is 0(*) . 3. [ 15 pts ] Suppose n >1 and m >1 are integers and n I m. Show for integers a and b that if a b (mod m), then a b (mod n) 4. [ 15 pts ] Show that if a b (mod m) and c with m 2, then a-c b-d (mod m). d (mod m), where a, b, c, d, and m are integers 5. [ 20 pts ] Prove that if n is an odd positive integer, then n2(mod 8)