5.5-5.6 Function Operations and Inverses

f(x) = 5x - 7

g(x) = 3x + 10

Find (f + g)(x).

• 8x² + 3

• 8x + 3

• 8x - 3

• 15x² - 70

f(x) = x² - 5x - 8

g(x) = 4x² - x + 3

Find (f + g)(x).

• 5x⁴ - 6x² - 5

• 4x² + 5x + 5

• 4x² + 5x - 5

• 5x² - 6x - 5

f(x) = 4x+8

g(x) = x+3,

Find (fg)(x)

• 4x²+24

• 4x²+20x+24

• 4x²+12x+24

• 4x²+4x+24

Are these inverse functions?

• no
• yes
• no way to tell

Are the blue and red graphs inverse functions?

• Yes, the functions reflect over y = x

• No, they do not reflect over the x - axis.

• No way to tell from a graph

The inverse of a function has been reflected over which line?

• y = x

• y =1

• y = 0

• y = x + 1

What is the inverse of the given relation? {(1, 2) (3, 8) (-3, 6)}

• (1, 2) (3, 8) (-3, 6)

• (1, 2) (8, 3) (-3, 6)

• (-1, -2) (-3, -8) (3, -6)

• (2, 1) (8, 3) (6, -3)

When finding the inverse of a relation, 
1st you replace f(x) with y
2nd switch the x's and y's
What do you do next?

• solve for y
• replace y with f^-1(x)
• solve for x
• find the greatest common factor