Saturday

February 28, 2015

February 28, 2015

Posted by **jeep** on Thursday, April 1, 2010 at 4:11pm.

1, 4, 9, 16, 25, . . . The pentagonal numbers 1, 5, 12, 22, 35, . . .. The geometrical language is

justified by the following diagrams:

a. What are the first five hexagonal numbers? What are the first five septagonal numbers?

What are the first five r-gonal numbers? Give a formula for the nth triangular number.

Give a formula for the nth square number. Give a formula for the nth pentagonal number.

In general, give a formula for the nth r-gonal number.

b. How many numbers can you find that are simultaneously triangular and square? How

many numbers can you find that are simultaneously square and pentagonal?

10. The tail of a giant kangaroo is attached by a giant rubber band to a stake in the ground. A

**Answer this Question**

**Related Questions**

MATH - The triangular numbers are the numbers 1, 3, 6, 10, 15, . . .; the square...

Math - Mark read that the ancient Greeks use to arrange pebbles to represent ...

9th grade - Name the set(s) of numbers to which 1.68 belongs. a. rational ...

math - list all numbers from the given set {-9,-4/5,0,0.25,/3,9.2,/100} that are...

AiMS MATH - -5 Is A Member Of Which Subset Of Real Numbers. a) natural numbers b...

algebra - List all the numbers from the given set that are, a.natural numbers b....

Math - Which expression is equivalent to (-2)(a+6)? -2a+6 2a+12*** -2a-12 -2a+12...

Algebra - To which subset of rel numbers does the number -22 belong? whole ...

math URGENT!!!! - i have a list of 5 different numbers. the sum of 2 of the ...

Math - Hot numbers in a lottery are numbers that keep coming up. Cold numbers ...