find any critical numbers for f and then use the second derivative test to decide whether the critical…

find any critical numbers for f and then use the second derivative test to decide whether the critical number(s) lead to relative maxima or relative minima. if f(c)=0 or f(c) does not exist for a critical number c, then the second derivative test gives no information. in this case, use the first derivative test instead.\nf(x)=-x² - 10x + 24\nwhat is/are the critical number(s)? select the correct choice below and, if necessary, fill in the answer box to complete your choice.\na. the critical number(s) is/are x = (simplify your answer. use a comma to separate answers as needed.)\nb. there are no critical numbers.\nwhere are the relative extrema? select the correct choice below and, if necessary, fill in the answer box(es) to complete your choice.\na. the function has a relative minimum at x = (simplify your answer. use a comma to separate answers as needed.) there are no relative maxima.\nb. the function has a relative maximum at x = (simplify your answer. use a comma to separate answers as needed.) there are no relative minima.\nc. the function has a relative minimum at x = and a relative maximum at x = (simplify your answers. use a comma to separate answers as needed.)\nd. there are no relative extrema.
Answer
Explanation:
Step1: Find the first derivative
The function is ( f(x)=-x^{2}-10x + 24 ). Using the power rule ( (x^{n})^\prime=nx^{n - 1} ), we have ( f^\prime(x)=-2x-10 ). Set ( f^\prime(x) = 0 ): ( -2x-10=0 ) ( -2x=10 ) ( x=-5 )
Step2: Find the second derivative
Differentiate ( f^\prime(x)=-2x - 10 ) with respect to ( x ). Using the power rule, ( f^{\prime\prime}(x)=-2 ).
Step3: Apply the second - derivative test
Since ( f^{\prime\prime}(-5)=-2<0 ), by the second - derivative test, when ( f^{\prime}(c) = 0 ) and ( f^{\prime\prime}(c)<0 ), the function ( f(x) ) has a relative maximum at ( x = c ).
Answer:
- Critical number: ( A. ) The critical number(s) is/are ( x=-5 )
- Relative extrema: ( B. ) The function has a relative maximum at ( x=-5 )