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Find-f-0-when-a-polynomial-f-x-satisfies-lim-x-1-f-x-x-2-1-2-lim-x-1-f-x-x-2-1-2-lim-x-f-x-x-4-1-pls-Help-




Question Number 94214 by abony1303 last updated on 17/May/20
Find f(0) when a polynomial f(x) satisfies  lim_(x→1)  ((f(x))/(x^2 −1))=2  lim_(x→−1)   ((f(x))/(x^2 −1))=2    lim_(x→+∞)   ((f(x))/x^4 ) =1        pls Help!
Findf(0)whenapolynomialf(x)satisfieslimx1f(x)x21=2limx1f(x)x21=2limx+f(x)x4=1plsHelp!
Commented by john santu last updated on 17/May/20
lim_(x→+∞)  ((f(x))/x^4 ) = ??
limx+f(x)x4=??
Commented by john santu last updated on 17/May/20
f(x) = (x^2 −1)(ax^2 +b)
f(x)=(x21)(ax2+b)
Commented by abony1303 last updated on 17/May/20
changed
changed
Commented by i jagooll last updated on 17/May/20
f(x)=(x^2 −1)(ax^2 +bx+c)  (1) lim_(x→1)  (((x^2 −1)(ax^2 +bx+c))/(x^2 −1)) = 2  ⇒a+b+c = 2  (2) lim_(x→−1)  (((x^2 −1)(ax^2 +bx+c))/(x^2 −1)) = 2  ⇒ a−b+c = 2  (3) lim_(x→+∞) ((f(x))/x^4 ) = 1 ⇒ a = 1   eq (1)+(2) ⇒ 2a+2c = 4 ⇒ c = 1 and   b = 0 . then f(x) = (x^2 −1)(x^2 +1)  f(0) = −1
f(x)=(x21)(ax2+bx+c)(1)limx1(x21)(ax2+bx+c)x21=2a+b+c=2(2)limx1(x21)(ax2+bx+c)x21=2ab+c=2(3)limx+f(x)x4=1a=1eq(1)+(2)2a+2c=4c=1andb=0.thenf(x)=(x21)(x2+1)f(0)=1

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