Hello :
all n in N ; n(n+1)(n+2) = 3a a in N or : <span>≡ 0 (mod 3)
1 ) n </span><span>≡ 0 ( mod 3)...(1)
n+1 </span>≡ 1 ( mod 3)...(2)
n+2 ≡ 2 ( mod 3)...(3)
by (1), (2), (3) : n(n+1)(n+2) ≡ 0×1×2 ( mod 3) : ≡ 0 (mod 3)
2) n ≡ 1 ( mod 3)...(1)
n+1 ≡ 2 ( mod 3)...(2)
n+2 ≡ 3 ( mod 3)...(3)
by (1), (2), (3) : n(n+1)(n+2) ≡ 1×2 × 3 ( mod 3) : ≡ 0 (mod 3) , 6≡ 0 (mod)
3) n ≡ 2 ( mod 3)...(1)
n+1 ≡ 3 ( mod 3)...(2)
n+2 ≡ 4 ( mod 3)...(3)
by (1), (2), (3) : n(n+1)(n+2) ≡ 2×3 × 4 ( mod 3) : ≡ 0 (mod 3) , 24≡ 0 (mod3)
Answer:19
Step-by-step explanation: 380 divide by 20 is 19
give me brainliest please
D the sent greater than or equal to 1
Answer:
5.83 inches
Step-by-step explanation:
The card is a rectangular shaped object, drawing a diagonal from one corner to the other, divides the rectangle into two right angled triangles with the diagonals as the hypothenuse.
Using Pythagoras theorem.
c^2 = a^2 + b^2
Given;
Side a = 3
Side b = 5
Substituting the given values;
c^2 = 3^2 + 5^2
c = √(9+25)
c = √34
c = 5.83 inches