(1) We know that 1 + 3 = 4 = 2, 1 + 3 + 5 = 9 = 3, 1 + 3 + 5 + 7 + 9 = 25 = 5 Following the example above, calculate 1 + 3 + 5 + 7 + +99=? According to the above rule, please use the natural number n (n is greater than or equal to 1) to express the general rule (2) Look at the following equation. Please use the equation about n to show the law you found 9-1=8,16-4=12,25-9=16,36-16=20…… (3) Given that the square of (2x-1) = the square of AX + BX + C, find the value of a + C, 4A + B + 4C

(1) 2500 1+3+5+7+9+（2n-1)=n^2
(2)(n+2)^2-n^2=4(n+1)
(3)4x^2-4x+1=ax^2+bx+c
a=4 b=-4 c=1
a+c=5 4a+b+4c=16

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