If one root of the quadratic equation AX ^ 2 + BX + C = 0 is greater than 1 and the other root is less than 1, then the value of a + B + C is

If one root of the quadratic equation AX ^ 2 + BX + C = 0 is greater than 1 and the other root is less than 1, then the value of a + B + C is

If f (1) = 0, it means that 1 is also a root of the quadratic equation with one variable. In the design of the problem, it is clearly pointed out that the two roots of the equation, one is greater than 1, the other is less than 1, and the quadratic equation with one variable has at most two roots So f (1) can't be 0, but we can judge that f (1) is not 0. If we give such a condition, we can't get the value of F (1) = a + B + C
Take two examples to prove that, for example, the two roots of x ^ 2-2x-3 = 0 are 3 > 1, and - 11, and - 1, respectively

7:8=24:( )
3:( )=9:4

7:8=24:( 192/7 )
3:( 4/3 )=9:4

A math problem, there are two ropes, the first one uses 1 / 5 meter, the second one uses 1 / 5 of it, the rest are equal, so which rope is long?

If it's all one meter, it's the same length