Can someone please help with this question please? Thanks!

3^667 * 2^2 = X * 10^Y

I need to find X and Y. I.e. convert to scientific notation. Thanks!

And this one too.

2^10^6 = X * 10^Y

Find X & Y.

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- October 21st 2005, 11:19 PMphgaoHow many tens?
Can someone please help with this question please? Thanks!

3^667 * 2^2 = X * 10^Y

I need to find X and Y. I.e. convert to scientific notation. Thanks!

And this one too.

2^10^6 = X * 10^Y

Find X & Y. - October 22nd 2005, 12:31 AMniva
I don't know if my answer is good enough for you.

As I learned from limit taking techniques of calculus, when there are power look like things in the equation, take log on both sides won't change the equality of the equation.

For the second equation of your question, take natural log on both sides, get:

ln(2^10^6)=ln(x*10^y)

ln(10^6)/ln(2)=ln(x)+ln(10^y)

ln(10^6)/ln(2)=ln(x)+y*ln(10)

now you have a y times something - October 22nd 2005, 03:02 AMphgao
Nope that wasn't what I was looking for. Thanks anyway.

- October 23rd 2005, 12:26 AMticbolQuote:

3^667 * 2^2 = X * 10^Y

I need to find X and Y. I.e. convert to scientific notation. Thanks!

And this one too.

2^10^6 = X * 10^Y

Find X & Y.

10^a = b ----------------------------------(i)

Take the common logs of both sides,

a*log(10) = log(b)

a*1 = log(b)

a = log(b)

Substitute thjat back into (i),

10^(log(b)) = b

Or,

b = 10^log(b) -----------(ii), where log is logarithm to the base 10.

So,

3^667 = [10^log(3)]^667 = 10^[667*log(3)]

2^2 = [10^log(2)]^2 = 10^[2*log(2)]

Then,

(3^667)*(2^2)

= 10^[667log(3)] *10^[2log(2)]

= 10^{667log(3) +2log(2)}

Using a calculator,

= 10^318.8419369 -----***

= 10^318 *10^0.8419369

= 10^318 *6.949233427

= 6.949233427 *10^318 ----------***

Therefore, in [3^667 * 2^2 = X * 10^Y],

X = 6.949233427, and Y = 318. ---------------answer.

---------------

2^10^6 = X * 10^Y

2^10^6

= (2^10)^6

= 2^(10*6)

= 2^60 -------------***

= [10^log(2)]^60

= 10^ 60log(2)

= 10^ 18.06179974

= 10^18 *10^0.06179974

= 10^18 *1.152921505

= 1.152921505 *10^18 --------***

Therefore, in [2^10^6 = X * 10^Y],

X = 1.152921505, and Y = 18. -----------------answer. - October 24th 2005, 10:38 PMphgao
Thanks a lot ticbol!