56$ hope that helped also.......................
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.
Assuming you want to choose 4 people from the class of 20;
Begin by using the combinations formula;
20C4=4845 possibilities
Hope I helped :)
Answer:
•12.12
•56.92
Step-by-step explanation:
•Sin 30° = x ÷ 14√3
x=14√3 *Sin30
x=7√3
x=12.12
•Tan30°=6√3÷x
x=6√30 ÷Tan 30
x=18√10
x=56.92
