SOLUTION: (3z^4 - 8)^2

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Question 183219: (3z^4 - 8)^2
Found 2 solutions by jim_thompson5910, stanbon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

%283z%5E4-8%29%5E2 Start with the given expression.


%283z%5E4-8%29%283z%5E4-8%29 Expand. Remember something like x%5E2=x%2Ax.


Now let's FOIL the expression.


Remember, when you FOIL an expression, you follow this procedure:


%28highlight%283z%5E4%29-8%29%28highlight%283z%5E4%29-8%29 Multiply the First terms:%283%2Az%5E4%29%2A%283%2Az%5E4%29=9%2Az%5E8.


%28highlight%283z%5E4%29-8%29%283z%5E4%2Bhighlight%28-8%29%29 Multiply the Outer terms:%283%2Az%5E4%29%2A%28-8%29=-24%2Az%5E4.


%283z%5E4%2Bhighlight%28-8%29%29%28highlight%283z%5E4%29-8%29 Multiply the Inner terms:%28-8%29%2A%283%2Az%5E4%29=-24%2Az%5E4.


%283z%5E4%2Bhighlight%28-8%29%29%283z%5E4%2Bhighlight%28-8%29%29 Multiply the Last terms:%28-8%29%2A%28-8%29=64.


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So we have the terms: 9%2Az%5E8, -24%2Az%5E4, -24%2Az%5E4, and 64


9%2Az%5E8-24%2Az%5E4-24%2Az%5E4%2B64 Now collect every term listed above to make a single expression.


9%2Az%5E8-48%2Az%5E4%2B64 Now combine like terms.


So %283z%5E4-8%29%5E2 FOILs to 9%2Az%5E8-48%2Az%5E4%2B64.


In other words, %283z%5E4-8%29%5E2=9%2Az%5E8-48%2Az%5E4%2B64.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
(17:21:47): (3z^4 - 8)^2
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[17/(21/47)) / (3z^4 - 8)^2
= [(17*47)21] / (9z^8 - 2*8*3z^4 + 64)
= [38.048] / [9z^8 - 48z^4 + 64]
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Cheers,
Stan H.