Joe_Rovalino_R_Studio_wk#1

R Bridge Week 1 Assignment Please create the following exercises in .rmd format, publish to rpub and submit both the .rmd file and the rpub link. 1. Write a loop that calculates 12-factorial 2. Show how to create a numeric vector that contains the sequence from 20 to 50 by 5. 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

1. Write a loop that calculates 12-factorial

i <- 1
for (i in 1:12) {
 Ans <- print(c("Number" = i,"Factorial" = factorial(i)))
  Ans
}

##    Number Factorial 
##         1         1 
##    Number Factorial 
##         2         2 
##    Number Factorial 
##         3         6 
##    Number Factorial 
##         4        24 
##    Number Factorial 
##         5       120 
##    Number Factorial 
##         6       720 
##    Number Factorial 
##         7      5040 
##    Number Factorial 
##         8     40320 
##    Number Factorial 
##         9    362880 
##    Number Factorial 
##        10   3628800 
##    Number Factorial 
##        11  39916800 
##    Number Factorial 
##        12 479001600

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

r <-seq(20,50,by=5)
r

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

3. Create the function “quadratic” 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

quadratic <- function(a,b,c){ 

  output <- (-b + c(-1,1) * sqrt(b^2-4*a*c))/2*a;
output

} 
  
quadratic(1,-2,1)

## [1] 1 1

# x=-b/(2*a) so =0 roots will be 1
quadratic(1,-4,1)

## [1] 0.2679492 3.7320508

quadratic(4,-1,5)

## Warning in sqrt(b^2 - 4 * a * c): NaNs produced

## [1] NaN NaN

#NaN is produced for the last test as a result of the b^2-4*a*c < 0