11 Replies Latest reply: Feb 18, 2011 10:55 AM by A.Non

# Decimal Number and Solving Equation.

Hello,

I have a question and wish learning. It's about "Decimal Number and Solving Equation"

Solve,x.

Regards,

Loi.

• ###### Re: Decimal Number and Solving Equation.

Like below.

Mike

• ###### Re: Decimal Number and Solving Equation.

Assuming that all those digits in the starting equation are actually valid, you are better off using the symbolic processor to solve it. It's more accurate.

• ###### Re: Decimal Number and Solving Equation.

Thanks for your help, Mike and Richard. I follow Richard's instruction and :

(1)

(2)

from (1) & (2) above, what we could say between :

or

Regards,

Loi.

Message was edited by: Loi Le

• ###### Re: Decimal Number and Solving Equation.

I don't quite understand what your after. Can you elaborate?

Mike

• ###### Re: Decimal Number and Solving Equation.

After solve, then substitute, x=0 above. We get :

( That means : True ) (7)

( That means : True , also ) (8)

from (7) & (8) above =>

or

Thanks again.

• ###### Re: Decimal Number and Solving Equation.

Sorry maybe it's me - it is getting past my bed time.

I still don't understand what your after.

Mike

• ###### Re: Decimal Number and Solving Equation.

Of course the two numbers are not strictly equal. You can tell that just by looking at them. You just don't have enough precision in the calculations to see the difference.

By default, the symbolic processor uses 20 digits of precision for floating point calculations. You can change that by using the float keyword (which does not just change the precision of the displayed result; it changes the precision used in the calculations).

• ###### Re: Decimal Number and Solving Equation.

I greatly appreciate your answer to my question, Richard. (A nice answer). I think I am new and have not comprehended with "float,50 ,..". Could you tell me more elaborate (as Mike said above) the following :

Regards,

Loi.

• ###### Re: Decimal Number and Solving Equation.

That expression is actually a very good example to show what the float keyword does. See the attached.

• ###### Re: Decimal Number and Solving Equation.

I got it. Many thanks, Richard. And I have one more related question :

Is there a "cheat" way by keystroke to simflify is equivalent to another ?

Regards,

Loi.

• ###### Re: Decimal Number and Solving Equation.

Is there a "cheat" way by keystroke to simflify is equivalent to another ?

I'm not sure what you mean. Do you mean "can it be simplified to another equivalent expression?". No. At least, not by either the Maple of the Mupad engines in MC11 and MC15. If you type ,max (note the comma!) after the keyword simplify it will give you the maximum amount of simplification the symbolic processor can do.