f(x)=2x^5 +x^4 - 5 find f" (1)?

4 ⤊

2007-11-23 06:32:33 · 4 answers · asked by nafiseh g 1 in Science & Mathematics ➔ Mathematics

f `(x) = 10x^4 + 4 x ³
f "(x) = 40 x ³ + 12 x ²
f "(1) = 40 + 12 = 52

2007-11-23 06:49:36 · answer #1 · answered by Como 7 · 2⤊ 1⤋

f(x)=2x^5 +x^4 - 5
fÎ(x)=10x^4+4x^3
fÎÎ(x)=40x^3+12x^2
fÎÎ(1)=40*1^3+12*1^2=
=40+12=52

2007-11-23 14:36:59 · answer #2 · answered by Kulubaki 3 · 0⤊ 2⤋

f'(x) = 10x^4 + 4X^3
f''(X) = 40x^3 +12X^2
=> f''(1)=40(1) + 12(1) = 52

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2007-11-23 14:36:40 · answer #3 · answered by None 2 · 0⤊ 2⤋

f''(1) = 40 + 12 = 52
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Ideas: (2x^5)'' = 2*5*4x^3 and (x^4)'' = 4*3x^2

2007-11-23 14:35:41 · answer #4 · answered by sahsjing 7 · 2⤊ 0⤋