First observe the following formula, fill in the blanks and summarize the rules 3²-1²=8×1, 5²-3²=8×2; Then (1) 7 & sup2; - 5 & sup2; = 8 × (3) (2)9²-(7)²=8×4 (3)(11)²-9²=8×5 Sum up the law____________________________________ .

First observe the following formula, fill in the blanks and summarize the rules 3²-1²=8×1, 5²-3²=8×2; Then (1) 7 & sup2; - 5 & sup2; = 8 × (3) (2)9²-(7)²=8×4 (3)(11)²-9²=8×5 Sum up the law____________________________________ .

N & sup2; - (n-2) & sup2; = 8 × (n-1) / 2 n is an odd number not less than 3?