Question

49. If y = a log x + bx² + x has its extremum value at x = -1 and x = 2, then
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Answer 1

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=> a = 2 and b = -1/2

y = a log x + bx² + x has its extremum value at x = -1 and x = 2

dy/dx = 0 at x = -1 and x = 2

=> a/x + 2bx + 1 = 0, at x = -1 and x = 2

-a - 2b + 1 = 0 and a/2 + 4b + 1 = 0

=> a = 2 and b = -1/2

silentlover45.❤️

Answer 2

Answer:

=> a = 2 and b = -1/2

y = a log x + bx² + x has its extremum value at x = -1 and x = 2

dy/dx = 0 at x = -1 and x = 2

=> a/x + 2bx + 1 = 0, at x = -1 and x = 2

-a - 2b + 1 = 0 and a/2 + 4b + 1 = 0

=> a = 2 and b = -1/2