HIGH SCHOOL STUDY HELP
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Please help me with this question :)
Hi,
Thank you for your question.
First, we should be finding the critical points of the function (where the derivative of the function equals zero):
f ' (x) = { (2x)(x+2) - (x^2+3) } / ( (x+2)^2 )
f ' (x) = ( x^2 + 4x - 3 ) / ( (x+2)^2 )
First critical point you may see is x = -2, but this value is not in the domain, so ignore this.
Other critical points are when x^2 + 4x - 3 = 0. Using the quadratic equation, x = -2 + sqrt (7), -2 - sqrt (7).
Similarly, as -2 + sqrt(7) is not in the domain, the only relevant critical point is when x = -2 - sqrt (7).
Afterwards, we can check some points.
a) f ( -2 - sqrt (7) ) = -2sqrt(7) - 4
b) As x gets really close to -7 (right side limit), f(x) approaches negative infinity.
c) As x gets really close to -2 (left side limit), f(x) approaches negative infinity.
Therefore, there is no absolute minimum on the given interval. On the other hand, there is an absolute maximum of -2sqrt(7) - 4 when x = -2 - sqrt(7).
Does this answer your question?
Hi,
Thank you for your question.
First, we should be finding the critical points of the function (where the derivative of the function equals zero):
f ' (x) = { (2x)(x+2) - (x^2+3) } / ( (x+2)^2 )
f ' (x) = ( x^2 + 4x - 3 ) / ( (x+2)^2 )
First critical point you may see is x = -2, but this value is not in the domain, so ignore this.
Other critical points are when x^2 + 4x - 3 = 0. Using the quadratic equation, x = -2 + sqrt (7), -2 - sqrt (7).
Similarly, as -2 + sqrt(7) is not in the domain, the only relevant critical point is when x = -2 - sqrt (7).
Afterwards, we can check some points.
a) f ( -2 - sqrt (7) ) = -2sqrt(7) - 4
b) As x gets really close to -7 (right side limit), f(x) approaches negative infinity.
c) As x gets really close to -2 (left side limit), f(x) approaches negative infinity.
Therefore, there is no absolute minimum on the given interval. On the other hand, there is an absolute maximum of -2sqrt(7) - 4 when x = -2 - sqrt(7).
Does this answer your question?