GSCE Maths Flashcards
even x even= even
even x odd= even
odd x odd= odd
even + even= even
even + odd= odd
odd + odd= even
(2n+1)+(2n+3)
4n+4
4(n+1)
proofs follow these formats
a number (n)
an even number 2(n)
an odd number 2(n)+1
even number example
2n+4(n+1)+4 is always even
2n+4n+4+4
6n+8
2(3n+4)
odd number example
4(2n-3)-3(2n-1) is always odd
8n-12-6n+3
2n-9
2(n-8)-1
the sum of two consecutive odd numbers, is always a multiple of 4
example
(2n+1)+(2n+3)
4n+4
4(n+1)
when x is even, (x-2)^2 is even
subtracting an even number keeps it even and any even number multiplied by any even number stays even
(x-2) is even, an even number squared is even
-2 and it stays even, x by itself and it stays even
even-even=even, even x even=even
even-even=even, and even x even/odd=even
ax^2+axc+x+b=5x^2+11x+8
ax^2+axc+x+b=5x^2+11x+8
a=5, b=6, c=2
prooving if a gradient is perpendicular
the two gradients multipled should equal -1
Float and ping
Escalator
Float and ping the number (e.g -3 or 2)
x/4=12 take 4 up the escalator
4x=12 take 4 down the escalator