Hello,
I would love to answer but there is no screenshot to see!
Answer:
Consider f: N → N defined by f(0)=0 and f(n)=n-1 for all n>0.
Step-by-step explanation:
First we will prove that f is surjective. Let y∈N be any natural number. Define x as the number x=y+1. Then x∈N, and f(x)=x-1=(y+1)-1=y. We conclude that f is surjective.
However, f is not injective. Take x1=0 and x2=1. Then x1≠x2 but f(x1)=0 and f(x2)=x2-1=1-1=0. We have shown that there are two natural numbers x1,x2 such that x1≠x2 but f(x1)=f(x2), that is, f is not injective.
Note:
If 0∉N in your definition of natural numbers, the same reasoning works with the function f: N → N defined by f(1)=1 and f(n)=n-1 for all n>1. The only difference is that you consider x1=1, x2=2 for the injectivity.
An angle adjacent to BOC would be COD or BAC.
Answer: 110, 35, 70, G, J, F, E, B, A, H, C, D, I
Step-by-step explanation:
8. For number 8, you will be using the exterior angle theorem. The exterior angle theorem states that the exterior angle equals the two angles inside the given triangle. Since we have 50 and 60, you will add 50 + 60 to get 110.
9. In this problem, you shall use the vertical angle theorem. The vertical angle theorem is simply that any angles vertical from one another are congruent. So a will be also 35 degrees.
10. This is an image depicting two lines cut by a transversal, creating multiple congruent angles. With this, you will be using the alternate interior angle theorem. Alternate interior angles are angles on different sides of the transversal but inside both of the lines that were cut into, as shown above. So, b will also equal 70 degrees.
Part B:
1. G
2. J
3. F
4. E
5. B
6. A
7. H
8. C
9. D
10. I
3 x 4 is equal to 12 I think that’s your answer