scientific notation world problem and 2 polynomial questions

ayva00

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Nov 29, 2008
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These are some homework problems i have that i'm a bit confused about.

simplify: 2(-50)^0-2^-3 so i did 2(1)-2^-3 then 2+8= 10, did i do that problem correctly?

write the coefficient of the third degree term of the polynomial in the blank: 5x^4-8x^3-6x+16, does the 3rd degree mean the 3rd polynomial or the polynomial with the exponent of 3. I'm thinking it's the the first option, so the answer would be -6.

and lastly this word problem,
Write the numbers one million and one millionth in scientific notation. By what number must we multiply one millionth to get one million?
So i wrote 1,000,000 and 1 x 10^6. So is the answer 6? or just 1 maybe? :/


Thanks so much, i really appreciate the help.
 

fasteddie65

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Nov 1, 2008
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"simplify: 2(-50)^0-2^-3 so i did 2(1)-2^-3 then 2+8= 10, did i do that problem correctly?"
No. 2^(-3) = 1/8 2 - 1/8 = 15/8

"write the coefficient of the third degree term of the polynomial in the blank: 5x^4-8x^3-6x+16, does the 3rd degree mean the 3rd polynomial or the polynomial with the exponent of 3. I'm thinking it's the the first option, so the answer would be -6."
The 3rd degree term is the term with a 3 exponent on the variable, so the answer is -8.

"and lastly this word problem,
Write the numbers one million and one millionth in scientific notation. By what number must we multiply one millionth to get one million?
So i wrote 1,000,000 and 1 x 10^6. So is the answer 6? or just 1 maybe? :/"
You write the numbers correctly. The number by which you multiply one millionth by to get one million is 1 • 10^12.
 

ayva00

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Nov 29, 2008
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The last two i understand, but the first one, i'm a little lost how you got the fraction. -2^-3 isnt going to be 8? or -8 even?
Sorry, i'm just trying to understand. Thanks for your help
 

Denis

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RULE: a^(-p) = 1 / a^p ; so 2^(-3) = 1 / 2^3
 

ayva00

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Nov 29, 2008
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Denis said:
RULE: a^(-p) = 1 / a^p ; so 2^(-3) = 1 / 2^3
I notice that you're not including the negative infront of the 2, is there a reason for that or are you just not writing it?
thanks
 

Denis

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That "negative" has nothing to do with the value of 2^(-3).
It simply means to subtract that value.
 

Subhotosh Khan

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Remember:

\(\displaystyle (-a)^n\)

is usually different from

\(\displaystyle -(a)^n\)
 

ayva00

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Nov 29, 2008
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Ohhh okay, i got it. Thanks so much
 
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