Candidates Test
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AP Calculus AB › Candidates Test
A continuous function $h$ on $0,3$ has critical points $x=1,2$. If $h(0)=2,h(1)=3,h(2)=1,h(3)=0$, where is the absolute maximum?
At $x=0$
At $x=0$ or $x=3$ only
At $x=1$
At $x=3$
At $x=2$
Explanation
This problem assesses the Candidates Test, which is used to find absolute extrema of a continuous function on a closed interval. To apply the Candidates Test, we evaluate the function at all critical points inside the interval and at the endpoints. Critical points are where the derivative is zero or undefined, potentially indicating local maxima or minima. Endpoints must be checked because the absolute extremum could occur there, even without a zero derivative. A tempting distractor might be choosing x=2, but h(2)=1 is less than h(1)=3, so it's not the maximum. Remember, the checklist for candidates is: list all critical points in the interval, include both endpoints, evaluate f at each, and compare the values to find the max or min.
A continuous function $h$ on $-1,7$ has critical points at $x=2,5$ with $h(-1)=3,h(2)=1,h(5)=4,h(7)=2$. Where is the absolute maximum?
$x=-1$
Cannot be determined from given information
$x=5$
$x=2$
$x=7$
Explanation
This problem requires applying the Candidates Test to find the absolute maximum of a continuous function on a closed interval. The Candidates Test guarantees finding absolute extrema by systematically checking all possible locations where they can occur. For function h on [-1,7], the candidates are the endpoints x = -1 and x = 7, plus the critical points x = 2 and x = 5. Evaluating at each candidate gives: h(-1) = 3, h(2) = 1, h(5) = 4, and h(7) = 2. The largest value is h(5) = 4, so the absolute maximum occurs at x = 5. A student might mistakenly choose x = -1 by only comparing endpoint values without considering critical points. To apply the Candidates Test: identify the interval and all critical points within it, create a complete list including both endpoints, evaluate the function at every candidate, then select the location yielding the maximum value.
A continuous function $v$ on $1,5$ has critical points at $x=2,4$ with $v(1)=-3,v(2)=-1,v(4)=0,v(5)=-2$. Where is the absolute maximum?
$x=1$
$x=2$
$x=4$
$x=5$
There is no absolute maximum on $[1,5]$
Explanation
This problem requires applying the Candidates Test to find the absolute maximum of a continuous function on a closed interval. The Candidates Test provides a systematic approach to finding absolute extrema by examining all critical points and endpoints. For function v on [1,5], we must check endpoints x = 1 and x = 5, along with critical points x = 2 and x = 4. The function values at these candidates are: v(1) = -3, v(2) = -1, v(4) = 0, and v(5) = -2. Since v(4) = 0 is the largest value (least negative), the absolute maximum occurs at x = 4. A common error would be choosing x = 2 by only comparing critical points or misunderstanding negative values. Remember the candidates checklist: compile all critical points within the interval, include both endpoints, evaluate the function at each candidate, then identify the location with the maximum (most positive or least negative) value.
A continuous function $u$ on $-5,1$ has critical points at $x=-4,-2$ with $u(-5)=0,u(-4)=-2,u(-2)=-1,u(1)=3$. Where is the absolute minimum?
$x=-2$
$x=-5$
$x=-4$
Cannot be determined from given information
$x=1$
Explanation
This problem requires applying the Candidates Test to find the absolute minimum of a continuous function on a closed interval. The Candidates Test ensures we find absolute extrema by checking all possible locations: endpoints and critical points within the interval. For function u on [-5,1], the candidates include endpoints x = -5 and x = 1, plus critical points x = -4 and x = -2. Evaluating at each candidate: u(-5) = 0, u(-4) = -2, u(-2) = -1, and u(1) = 3. The smallest value is u(-4) = -2, so the absolute minimum occurs at x = -4. Students might mistakenly choose x = -5 thinking the minimum must be at the left endpoint. To find extrema using the Candidates Test: identify all critical points within the interval, add both endpoints to your candidate list, evaluate the function at every candidate, then select the location yielding the extreme value.
A continuous function $s$ on $-3,3$ has critical points at $x=-2,1$ with $s(-3)=-1,s(-2)=2,s(1)=0,s(3)=1$. Where is the absolute maximum?
$x=3$
Cannot be determined from given information
$x=-2$
$x=1$
$x=-3$
Explanation
This problem requires applying the Candidates Test to find the absolute maximum of a continuous function on a closed interval. The Candidates Test provides a complete method for finding absolute extrema by examining all critical points and endpoints. For function s on [-3,3], the candidates are endpoints x = -3 and x = 3, along with critical points x = -2 and x = 1. Evaluating at each location: s(-3) = -1, s(-2) = 2, s(1) = 0, and s(3) = 1. The largest value is s(-2) = 2, so the absolute maximum occurs at x = -2. Students might mistakenly choose x = 3 by assuming the maximum must be at the right endpoint without checking all candidates. To apply the Candidates Test effectively: create a complete list of critical points within the interval, add both endpoints, evaluate the function at every candidate, then identify the location with the maximum value.
A continuous function $p$ on $1,9$ has critical points at $x=4,8$ with $p(1)=0,p(4)=2,p(8)=-3,p(9)=-1$. Where is the absolute minimum?
$x=4$
$x=1$
$x=8$
There is no absolute minimum on $[1,9]$
$x=9$
Explanation
This problem requires applying the Candidates Test to find the absolute minimum of a continuous function on a closed interval. The Candidates Test provides a systematic method to locate absolute extrema by examining all possible locations: critical points and interval endpoints. For function p on [1,9], we must check endpoints x = 1 and x = 9, along with critical points x = 4 and x = 8. The function values at these candidates are: p(1) = 0, p(4) = 2, p(8) = -3, and p(9) = -1. Since p(8) = -3 is the smallest value, the absolute minimum occurs at x = 8. Students might incorrectly select x = 1 if they only check endpoints or assume the minimum must be at the first critical point. The candidates method checklist: compile all critical points in the interval, add both endpoints to the list, evaluate the function at each candidate location, then identify where the minimum value occurs.
A continuous function $t$ on $2,8$ has critical points at $x=5,7$ with $t(2)=6,t(5)=4,t(7)=5,t(8)=3$. Where is the absolute minimum?
$x=8$
$x=7$
$x=2$
There is no absolute minimum on $[2,8]$
$x=5$
Explanation
This problem requires applying the Candidates Test to find the absolute minimum of a continuous function on a closed interval. The Candidates Test guarantees finding absolute extrema by systematically checking all locations where they can occur: critical points and endpoints. For function t on [2,8], we must evaluate at endpoints x = 2 and x = 8, and at critical points x = 5 and x = 7. The function values are: t(2) = 6, t(5) = 4, t(7) = 5, and t(8) = 3. Since t(8) = 3 is the smallest value among all candidates, the absolute minimum occurs at x = 8. A student might incorrectly choose x = 5 by only comparing critical points without considering endpoints. The candidates method for extrema: list all critical points in the open interval, include both endpoints of the closed interval, evaluate the function at each candidate, then select the location with the minimum value.
A continuous function $f$ on $-2,5$ has critical points at $x=0,3$ with $f(-2)=1,f(0)=4,f(3)=2,f(5)=0$. Where is the absolute maximum?
$x=3$
$x=-2$
$x=5$
Cannot be determined from given information
$x=0$
Explanation
This problem requires applying the Candidates Test to find the absolute maximum of a continuous function on a closed interval. The Candidates Test states that for a continuous function on a closed interval, the absolute extrema must occur either at critical points or at endpoints. We must check all candidates: the endpoints x = -2 and x = 5, and the critical points x = 0 and x = 3. Evaluating at each candidate: f(-2) = 1, f(0) = 4, f(3) = 2, and f(5) = 0. Since f(0) = 4 is the largest value among all candidates, the absolute maximum occurs at x = 0. A common error would be assuming the maximum must be at an endpoint without checking critical points. Remember the candidates checklist: identify all critical points in the interval, evaluate the function at all critical points and both endpoints, then select the location with the largest (or smallest) value.
A continuous function $f$ on $-2,4$ has critical points $x=0,3$. If $f(-2)=1,f(0)=5,f(3)=2,f(4)=0$, where is the absolute maximum?
At $x=4$
At $x=0$
At $x=3$
At $x=-2$
At $x=-2$ or $x=4$ only
Explanation
This problem assesses the Candidates Test, which is used to find absolute extrema of a continuous function on a closed interval. To apply the Candidates Test, we evaluate the function at all critical points inside the interval and at the endpoints. Critical points are where the derivative is zero or undefined, potentially indicating local maxima or minima. Endpoints must be checked because the absolute extremum could occur there, even without a zero derivative. A tempting distractor might be choosing x=3, but f(3)=2 is less than f(0)=5, so it's not the maximum. Remember, the checklist for candidates is: list all critical points in the interval, include both endpoints, evaluate f at each, and compare the values to find the max or min.
A continuous function $g$ on $-6,-2$ has critical points $x=-5,-3$. If $g(-6)=2,g(-5)=1,g(-3)=0,g(-2)=3$, where is the absolute minimum?
At $x=-2$
At $x=-6$ or $x=-2$ only
At $x=-3$
At $x=-6$
At $x=-5$
Explanation
This problem assesses the Candidates Test, which is used to find absolute extrema of a continuous function on a closed interval. To apply the Candidates Test, we evaluate the function at all critical points inside the interval and at the endpoints. Critical points are where the derivative is zero or undefined, potentially indicating local maxima or minima. Endpoints must be checked because the absolute extremum could occur there, even without a zero derivative. A tempting distractor might be choosing x=-5, but g(-5)=1 is greater than g(-3)=0, so it's not the minimum. Remember, the checklist for candidates is: list all critical points in the interval, include both endpoints, evaluate f at each, and compare the values to find the max or min.