R week1 HW

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This is Mengqin Cai’s Week 1 HomeWork for R.

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#1. Write a loop that calculates 12-factorial
factorial <- 1
for(i in 1:12){
factorial <-factorial*i
  }
factorial

## [1] 479001600

#2. Show how to create a numeric vector that contains the sequence from 20 to 50 by 5.
seq(from = 20, to = 50, by = 5)

## [1] 20 25 30 35 40 45 50

#3. Create the function “factorial” that takes a trio of input numbers a, b, and c and solve the quadratic
#equation. The function should print as output the two solutions.
  
factorial<-function(a,b,c){
    x1 <- (-b + sqrt(b*b-4*a*c))/(2*a)
    x2 <- (-b - sqrt(b*b-4*a*c))/(2*a)
    print(x1)
    print(x2)
  }
   factorial(1,-4,3)

## [1] 3
## [1] 1

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