1,-9,25,-49,_____,_______.找规律

问题描述:

1,-9,25,-49,_____,_______.找规律

81 -121
(-1)^(n+1)*(2n-1)²

1,-9,25,-49,__81___,___-121____.

1,-9,25,-49,81,-121
奇数的平方序列一正一负

81 -121

1=1^2
-9=-(3)^2
25=5^2
-49=-(7)^2
81=9^2
-121=-(11)^2
1,-9,25,-49,81,-121