Ex 6.3, 7 - Find both max, min value of 3x4 - 8x3 + 12x2 - Ex 6.3

part 2 - Ex 6.3,7 - Ex 6.3 - Serial order wise - Chapter 6 Class 12 Application of Derivatives
part 3 - Ex 6.3,7 - Ex 6.3 - Serial order wise - Chapter 6 Class 12 Application of Derivatives part 4 - Ex 6.3,7 - Ex 6.3 - Serial order wise - Chapter 6 Class 12 Application of Derivatives

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Ex 6.3, 7 Find both the maximum value and the minimum value of 3š‘„4 – 8š‘„3 + 12š‘„2 – 48š‘„ + 25 on the interval [0, 3].Let f(x) = 3š‘„4 – 8š‘„3 + 12š‘„2 – 48š‘„ + 25, where š‘„ ∈ [0, 3] Finding f’(š’™) f’(š‘„)=š‘‘(3š‘„^4 āˆ’ 8š‘„^3 + 12š‘„^2 āˆ’ 48š‘„ + 25)/š‘‘š‘„ f’(š‘„)=3 Ɨ4š‘„^3āˆ’8 Ɨ3š‘„^2+12 Ɨ2š‘„āˆ’48+0 f’(š‘„)=12š‘„^3āˆ’24š‘„^2+24š‘„āˆ’48 f’(š‘„)=12(š‘„^3āˆ’2š‘„^2+2š‘„āˆ’4) Putting f’(š’™)=šŸŽ 12(š‘„^3āˆ’2š‘„^2+2š‘„āˆ’4)=0 š‘„^3āˆ’2š‘„^2+2š‘„āˆ’4=0 š‘„^2 (š‘„āˆ’2)+2(š‘„āˆ’2)=0 (š‘„^2+2)(š‘„āˆ’2)=0 Since š‘„^2=āˆ’2 is not possible Thus š‘„=2 is only critical point Since are given interval š‘„ ∈ [0 , 3] Hence , calculating f(š‘„) at š‘„ = 0 , 2 & 3 Hence, Minimum value of f(š‘„) is –39 at š’™ = 2 Maximum value of f(š‘„) is 25 at š’™ = 0

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