# college algebra

posted by .

given the function f(x)= x^3+3x find the rate of chnge between the two values x:1 to 2

find the equation of a secant line containing the given points (1,f(1) and (2,f(2))

• college algebra -

f(1) = 4
f(2) = 14
rate of change = (14-4)/(2-1) = 10

the slope of the secant is 10, (see above)

equation is y = 10x + b
but (1,4) lies on it, so
4 = 10(1) + b
b = -6

secant equation: y = 10x - 6

## Similar Questions

1. ### Math 116

1.Write an equation of the line containing the given points and parallel to the given line (3,8); x+5y=3 2. Write an equation of the line containing the given points and parallel to the given line (-3,6); 5x=9y+2 3. Write an equation …
2. ### Math 116

1.Write an equation of the line containing the given points and parallel to the given line (3,8); x+5y=3 2. Write an equation of the line containing the given points and parallel to the given line (-3,6); 5x=9y+2 3. Write an equation …
3. ### calculus

Given the function f(x) = 3x - 9 a. Find the rate of change between the two stated values for x: 7 to 8 b. Find the equation of a secant line containing the given points: (7, f(7)) and (8, f(8))
4. ### math

can someone please help me with this question. Given the funtion f(x)= 3x-9 a. find the rate of change between the two stated values for x: 7 to 8 b. find the equation of a secant line containing the given points: (7,f(7)) and (8,f(8)) …

6. ### college algebra

given the functionf(x)=x^3+3x find the rateof change between the two stated values for x:1 to 2 find the equation of a secant line containig the given points (1,f(1))and (2,f(2))