Given Q (0,4), P is the minimum absolute value of PQ at any point on y = x ^ 2 + 1

Given Q (0,4), P is the minimum absolute value of PQ at any point on y = x ^ 2 + 1

Because P is a point on y = x ^ 2 + 1, let P (x, x ^ 2 + 1)
So PQ ^ 2 = x ^ 4-5x ^ 2 + 9 = (x ^ 2-2.5) ^ 2 + 11 / 4
So the minimum value of PQ ^ 2 is 11 / 4, so the minimum value of PQ is 11 / 4 under the root