how many intergers can be written with three 9's?
examples:
4480 = 9! / (9x9)
720 = 9*(square root of 9) - 9
this is an extra credit question for my math class. help please. thank you
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how many intergers can be written with three 9's?
examples:
4480 = 9! / (9x9)
720 = 9*(square root of 9) - 9
this is an extra credit question for my math class. help please. thank you
you don't tell us enough. Are the functions tan, cos, sin, etc allowed? What operators are allowed? How many parentheses? It sounds like this is a tedious assignment friend. If she is including everything, the possibilities are mind boggling. I would suggest studying for the next test rather than trying this.
There is another past thread similar to this.
Let me see if I can dig it up,
Plisken, What are you talking about?
9 + 9 + 9=27
9 + 9 - 9=9
9 - 9 + 9=9
9 - 9 - 9=nope
9 + 9 / 9=10 or 2
9 + 9 * 9=162 or 90
9 - 9 / 9=0 or 8
9 - 9 * 9=0 or nope
9 / 9 + 9=10
9 * 9 + 9=90 or 162
9 / 9 - 9=undefined or nope
9 * 9 - 9=72 or 0
9 / 9 / 9=nope
9 / 9 * 9=9 or nope
9 * 9 / 9=9
9 * 9 * 9=729
then you have all the permutations with ^ ! ln log sqrt (which shouldn't be legal since it's ^(1/2), and a variety of other math functions.
9! shouldn't be allowed either (9 x 8 x 7 x ... )...