It is known that a = 2x and B is a polynomial. When calculating B + A, Xiao Mahu regarded B + A as B △ a, and the result was X. thank you,

It is known that a = 2x and B is a polynomial. When calculating B + A, Xiao Mahu regarded B + A as B △ a, and the result was X. thank you,

B = 2x square. A + B = 2x + (2x Square) = 2x (x + 1)

Calculate ① (X-2) (X & # 178; + X-5) - 3x & # 179; ② (2a-b) (A & # 178; - 2Ab + 3B & # 178;)

①(x-2)(x²+x-5)-3x³
=x³+x²-5x-2x²-2x+10-3x³
=-2x³-x²-7x+10
②
(2a-b)(a²-2ab+3b²)
=2a³-4a²b+6ab²-a²b+2ab²-3b³
=2a³-5a²b+8ab²-3b³

It is known that the square + 2x-a + 1 = 0 of the equation x about X has no real root. Try to judge whether the square + ax + a = 1 of the equation x about X must have two unequal real roots

Because there are no real numbers
So 4-4 (1-A)

Quadratic equation x ^ 2 + ax-2a ^ 2 = 0
Can we find the root of real number

x^2+ax-2a^2=0
x^2 + ax + (2a)*(-a)=0
(x+2a)*(x-a)=0
x1=-2a
x2=a

It is known that α and β are the two roots of the quadratic equation x square + 2x-7, then the value of α square + 3 α + β is?

According to the relationship between root and coefficient, α + β = - 2
From α is the root of the equation, substituting into the equation: α ^ 2 + 2 α - 7 = 0
So: α ^ 2 + 3 α + β = (α ^ 2 + 2 α - 7) + (α + β) + 7 = 0-2 + 7 = 5

It is known that the quadratic equation of one variable x square + 2x-a = 0 with respect to X has two equal real roots

There are two equal real roots
∴△=b^2-4ac=0
2^2-4*1*(-a)=0
4+4a=0
a=-1

In the case of one variable quadratic equation x square + X + 2 = 0 root

There is no real root

It is known that the line y = ax-3a intersects with the line y = BX + B at point a (1,5 / 2). Find the solution set of the inequality BX + b > ax-3a > 0

First, a (1,5 / 2) is substituted into two linear equations to calculate a = - 5 / 4 and B = 5 / 4
Then we solve the inequality, and the solution set is (1,3)

If the solution set of inequality x ^ 2-ax + B is {x | 2 ＜ x ＜ 3}, find the solution set of inequality BX ^ 2-ax + 1 ＞ 0

By 21 / 2 or X1 / 2 or X

If the solution set of inequality ax ^ 2 + BX + 2 > 0 is {- 0.5,1 / 3}, then the value of a + B is

It can be seen from the meaning that: - 0.5 and 1 / 3 are the two roots of the quadratic equation AX ^ 2 + BX + 2 = 0
Inherent: 0.25a-0.5b + 2 = 0 a / 9 + B / 3 + 2 = 0
a=12,b=-10
a+b=2
But from the meaning of the title, we can see that the opening is downward, so "a" is changed to "a"“