Creating and manipulating expressions and formulae
-
-
problemLeftovers
Weekly Problem 26 - 2008
If $n$ is a positive integer, how many different values for the remainder are obtained when $n^2$ is divided by $n+4$? -
problemUnusual Long Division - Square Roots Before Calculators
However did we manage before calculators? Is there an efficient way to do a square root if you have to do the work yourself?
-
problemFactor List
Tina has chosen a number and has noticed something about its factors. What number could she have chosen? Are there multiple possibilities?
-
problemSixational
The nth term of a sequence is given by the formula n^3 + 11n. Find the first four terms of the sequence given by this formula and the first term of the sequence which is bigger than one million. Prove that all terms of the sequence are divisible by 6.
-
problemSnookered
In a snooker game the brown ball was on the lip of the pocket but it could not be hit directly as the black ball was in the way. How could it be potted by playing the white ball off a cushion?
-
problem'tis Whole
Take a few whole numbers away from a triangle number. If you know the mean of the remaining numbers can you find the triangle number and which numbers were removed?
-
problemThree Ways
If x + y = -1 find the largest value of xy by coordinate geometry, by calculus and by algebra.
-
problemPair Squares
The sum of any two of the numbers 2, 34 and 47 is a perfect square. Choose three square numbers and find sets of three integers with this property. Generalise to four integers.
-
problemDiverging
Show that for natural numbers x and y if x/y > 1 then x/y>(x+1)/(y+1}>1. Hence prove that the product for i=1 to n of [(2i)/(2i-1)] tends to infinity as n tends to infinity.