On what interval(s) of x does f have positive concavity? On what interval(s) of x does f have negative concavity?

Step-by-step explanation:

Concavity of a quadratic function is determined the leading coefficient.

If the leading coefficient is positive, graph will entirely concave upwards.

If the leading coefficient is negative, graph will concave downwards entirely.

So in the interval (-∞, ∞) function has the positive concavity.

There is no interval in which the given function has the negative concavity.

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step-by-step explanation:

1+2+3+4+5+6+7+8+9+10 = 55

2*10 = 20

55-20 = 35