A blog of tips and recommendations for anyone interested in learning or teaching mathematics.

Wednesday, June 17, 2015

More fun with Common Core and exponents

After the last post, I decided to follow some of the linksGary Rubinstein provided to see if the other lessons covering exponents were as bad as the examples he chose.

There is this odd thing that if the base is negative there is a space before the exponent but if the base is positive there isn't a space before the exponent. It's seems like the space is a formatting convention meant to represent brackets.

It seems incredible silly, it's just too easy to mistake (-x)^y with -(x^y) i.e. -x^y and -x^ y

There is this odd thing that if the base is negative there is a space before the exponent but if the base is positive there isn't a space before the exponent. It's seems like the space is a formatting convention meant to represent brackets.

ReplyDeleteIt seems incredible silly, it's just too easy to mistake (-x)^y with -(x^y) i.e. -x^y and -x^ y

That's an interesting observation about the formatting, though I think the operative word is still "silly."

DeleteIn some systems, such as Excel, -1^.5 gets you an error. In others, such as Matlab, it gets you -1.

ReplyDeleteEven stranger, if you put 1 into cell A1 in Excel, the formula -A1^.5 still gives an error.