Answered

Westonci.ca is your go-to source for answers, with a community ready to provide accurate and timely information. Join our Q&A platform and connect with professionals ready to provide precise answers to your questions in various areas. Get immediate and reliable solutions to your questions from a community of experienced professionals on our platform.

An icicle drips at a rate that can be represented by the function f(x) = −x2 + 8x − 7, where 0 ≤ x ≤ 10 and x is the number of hours after the sun has risen. When f(x) is a negative number, the icicle is not dripping. Determine the values when the icicle starts and stops dripping.

Sagot :

LammettHash

Find when f(x) = 0. By factorizing, we have

-x² + 8x - 7 = - (x - 7) (x - 1) = 0

so either x - 7 = 0 or x - 1 = 0, or simply x = 1 or x = 7.

Split the domain into three intervals, and check the sign of f(x) over each interval at some test point in the interval. The sign will tell you when the icicle is dripping (positive) or not (negative).

• [0, 1) : at x = 0, we have f(0) = -7 < 0

• (1, 7) : at x = 2, we have f(2) = 5 > 0

• (7, 10] : at x = 8, we have f(8) = -7 < 0

This tells us that the icicle is not dripping when 0 ≤ x < 1, begins to drip when x = 1, drips for the duration of 1 < x < 7, stops dripping when x = 7, and keeps on not dripping when 7 < x ≤ 10.

We appreciate your time. Please revisit us for more reliable answers to any questions you may have. We appreciate your time. Please come back anytime for the latest information and answers to your questions. Westonci.ca is here to provide the answers you seek. Return often for more expert solutions.