







Find the intersection of y=x1 and y=sin(x) 
20091010 

From Usama: There are many modern calculators and softwares that can plot the functions.
I have two very simple equations y=x1 and y=sin(x), if i draw them manually on paper i can not get the accurate value.
But i think a computer can easily draw perfect straight and curve lines so it should be easy to find the intersection point of two lines.
Is there any way or software that can tell the exact value of intersection point of two lines? Answered by Robert Dawson and Harley Weston. 





Alphanumeric addition 
20070701 

From JYOTI: the letters in the alphanumatic addition are all different. find the numbers indicated in codes. all letters are digits from 0 to 9. SEND+MORE=MONEY. Answered by Stephen La Rocque. 





If A is 1 and Z is 26 
20070629 

From Sue: If A is 1 and Z is 26 is there a word that when you multiply all the numbers instead of letters adds up to a million? Answered by Chris Fisher and Harley Weston. 





Finding square roots 
20070517 

From Chandler: I would like an easy way to find the square root of a number. Answered by Gabriel Potter. 





Successive differences 
20020120 

From Linsey: what is the rule for working out the formula for a sequence with three lines of difference? eg.
1, 3, 7, 15, 29
1st line differences: 2, 4, 8, 14
2nd line differences: 2, 4, 6
3rd line differences: 2, 2 Answered by Penny Nom. 





Numerical problems 
20011127 

From Yossi: I am preparing a 45 minutes class for K12 students. The problem is to show that algebraic equivalent expressions are not always numerically equivalent. In particular I would like to show one of these dangers: cancellation that occurs during the subtraction of nearly equal quantities. Do you have a good reference I could use to prepare my class. In particular to be able to show some examples and how one can avoid this type of error. I also would like to show examples with practical use. I tried to look up in the web but did not find anyhting appropriate. Answered by Chris Fisher. 





Find the rule 
20001027 

From Kelsa and Linda: Find the rule: It had 13 in a circle then 2 blank circles then 31 in a circle then two more blank circles. Could you please help us. Answered by Penny Nom. 

