1) 1/4+1/2
We need to convert the fractions.
1/4 is fine.
1 x 2=2
2 x 2=4
1/4+2/4=3/4
2) a+a
a can be written as 1a.
1a+1a=2a
I can't see photos and he doesn't know 3 or 4 and i'm confused on 5.
a=?
Hope it helps?
Answer:
−
4
n
−
5
Step-by-step explanation:
Simplify the expression.
9/100 = x/90
Cross multiply to get 810 = 100x
Divide both sides by 100 to get x = 81 inches
Proof by induction
Base case:
n=1: 1*2*3=6 is obviously divisible by six.
Assumption: For every n>1 n(n+1)(n+2) is divisible by 6.
For n+1:
(n+1)(n+2)(n+3)=
(n(n+1)(n+2)+3(n+1)(n+2))
We have assumed that n(n+1)(n+2) is divisble by 6.
We now only need to prove that 3(n+1)(n+2) is divisible by 6.
If 3(n+1)(n+2) is divisible by 6, then (n+1)(n+2) must be divisible by 2.
The "cool" part about this proof.
Since n is a natural number greater than 1 we can say the following:
If n is an odd number, then n+1 is even, then n+1 is divisible by 2 thus (n+1)(n+2) is divisible by 2,so we have proved what we wanted.
If n is an even number" then n+2 is even, then n+1 is divisible by 2 thus (n+1)(n+2) is divisible by 2,so we have proved what we wanted.
Therefore by using the method of mathematical induction we proved that for every natural number n, n(n+1)(n+2) is divisible by 6. QED.