Find b such that f(x)=-4x+bx+3 has a maximum value of 50?

Science & Mathematics by Anonymous 2018-06-21 14:02:13

Social Science

4 answers

Anonymous

f ` (x) = - 4 + b = 0 for a turning point b = 4
Anonymous

47 ≥ x(b-4)
Anonymous

We find where the slope f' = 0; so f' = -8x + b = 0 so that x = (b/8) is where the max occurs and f = - 4(b^2/64) + b^2/8 + 3 = 3b^2/16 + 3 = 50 max; then 3b^2 = 47*16 and b = sqrt(47*16/3) = 15.83 ANS
Anonymous

A non-constant line has no maximum.