R and Shiny: Pass inputs from sliders to reactive function to compute output

I have 6 parameters that the user can change values for. These are our 6 inputs. I want to create an output value that takes those 6 inputs and computes our value of interest given a number of related equations in a function. Here is what I have in my UI...

library(shiny)

# Define UI for slider demo application
shinyUI(pageWithSidebar(

#  Application title
headerPanel("# Header Title Goes Here"),

# Sidebar with sliders that demonstrate various available options
sidebarPanel(
# Simple integer interval
sliderInput("u1", "Name:", 
            min=0, max=10000, value=10000),
#There are 6 slider inputs...

    ),

# Show a table summarizing the values entered
mainPanel(
 tableOutput("values"),

 uiOutput("focal"))
 )
)  

Here is what I have in my server.R...

library(shiny)

shinyServer(function(input, output) {

# Reactive expression to compose a data frame containing all of the values
sliderValues <- reactive({

# Compose data frame
data.frame(
  Name = # Names of my 6 parameters,

  Value = # inputs based on my 6 values by `input$value`,

  stringsAsFactors=FALSE)
})

f <- renderText({function(r1, r2, r3, d1, d2, u1) #these are my 6 values
{ #List of equations that compute f based on the 6 values
}
})


# Show the values using an HTML table
output$values <- renderTable({
sliderValues()
})

# Show the final calculated value 
output$focal <- renderText({
f
})
})

I keep getting... Error: argument 1(type 'closure') cannot be handled by 'cat' and many other errors. I just don't how to transfer the updated user inputs of the 6 parameters to my function and spit that function back out in the output area on the Shiny html page.

Any help would be greatly appreciated!!

Thanks!