2x^3 + 4x^2 -7x +7 find points where it's tangent is zero?

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2x^3 + 4x^2 -7x +7 find points where it's tangent is zero?

ok... not a clue!! someone please help... i got... 6x^2+8x-7 , but where do i go from here??

2007-09-25 16:32:48 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics

3 answers

You are almost done. You found the derivative so you just need to find where it is zero. Since it is just a quadratic, use the quadratic formula to find the two roots. Good Luck!

2007-09-25 16:37:14 · answer #1 · answered by Anonymous · 0⤊ 0⤋

f `(x) = 6xÂ² + 8x - 7 = 0
x = [- 8 Â± â(64 +168)] / 12
x = [- 8 Â± â(232)] / 4
x = [- 8 Â± 4â(58)] / 4
x = [- 2 Â± â(58) ] / 4

2007-09-26 06:16:21 · answer #2 · answered by Como 7 · 2⤊ 0⤋

quadratic formula

2007-09-25 23:37:25 · answer #3 · answered by Marcus C 3 · 0⤊ 0⤋