Simple secondary function problem. Do me a favor~ Known parabola y = - 2x ^ 2-3 When x_______ Y increases with the increase of X; When x_______ Y decreases with the increase of X Then why can't we say it is: When x ≤ 0, y increases with the increase of X; When x ≥ 0, y decreases with the increase of X? That's why we can't include "0"? | Math enthusiast | Mathematical art

Simple secondary function problem. Do me a favor~ Known parabola y = - 2x ^ 2-3 When x_ Y increases with the increase of X; When x_ Y decreases with the increase of X Then why can't we say it is: When x ≤ 0, y increases with the increase of X; When x ≥ 0, y decreases with the increase of X? That's why we can't include "0"?

The symmetry axis of the function is x = - B / 2a, that is, Y axis
Because the quadratic coefficient is negative, the opening is downward,
When x 0, y decreases with the increase of X

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