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Please write a linear equation with one variable so that the coefficient of the unknown is - 2, and the solution of the equation is x = 0.5:1______ ．
When x = 0.5, - 2x = - 1, so the answer is: - 2x = - 1
The equation AX2 + 2x + 1 = 0 has at least one negative real root if and only if ()
A. 0 < a < 1b. 0 < a ≤ 1 or a < 0C. 0 ≤ a ≤ 1D. A ≤ 1
When a = 0, we get x = - 12. When a ≠ 0, it is obvious that the equation has no root equal to zero. If the equation has two real roots with different signs, we get a < 0 according to the relationship between the root and the coefficient; if the equation has two negative real roots, we get a < 0 according to the relationship between the root and the coefficient; 1A ＞ 0 − 2A ＜ 0 △ = 4 − 4A ≥ 0 0 ＜ a ≤ 1. To sum up, if the equation has at least one negative real root, then a ≤ 1. The equation AX2 + 2x + 1 = 0 of X has at least one negative real root if and only if a ≤ 1
The equation AX2 + 2x + 1 = 0 has at least one negative real root if and only if ()
A. 0 < a < 1b. 0 < a ≤ 1 or a < 0C. 0 ≤ a ≤ 1D. A ≤ 1
When a = 0, we get x = - 12. When a ≠ 0, it is obvious that the equation has no root equal to zero. If the equation has two real roots with different signs, we get a < 0 according to the relationship between the root and the coefficient; if the equation has two negative real roots, we get a < 0 according to the relationship between the root and the coefficient; 1A ＞ 0 − 2A ＜ 0 △ = 4 − 4A ≥ 0 0 ＜ a ≤ 1. To sum up, if the equation has at least one negative real root, then a ≤ 1. The equation AX2 + 2x + 1 = 0 of X has at least one negative real root if and only if a ≤ 1
RELATED INFORMATIONS
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