How Do Absolute Values Affect Solving Function Equations?

AI Thread Summary
Absolute values play a crucial role in solving function equations by requiring the consideration of different cases based on the input values. In the first example, the equation g(a) = 3a - 3 + |a + 5| must be set equal to 2a + 8, leading to the isolation of the absolute value expression. For the second example, h(x - 1) = |x| - 3(x - 1) + 4 necessitates substituting x - 1 into the function and solving for x. The key is to break down the absolute value based on whether the expression inside is positive or negative. Understanding these principles is essential for accurately solving equations involving absolute values.
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Homework Statement


I do not see how the two equations in each example are related, what should I do with them? (the l's are absolute value brackets):

a) Let g(x) = 3x - 3 + l x+5 l. Find all values of a which satisfy the equation:

g(a) = 2a +8


b) Let h(x) = l x l - 3x + 4. Find all solutions to the equation :

h(x - 1) = x - 2


I know how to find an equation of the following:

x + l 2x-1 l, find f(x) = 8

x + l 2x-1 l = 8

l 2x-1 l = 8-x

2x-1 = 8-x or -2x+1= 8-x
x=3 x=-7
 
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For part a, you have the formula for g(x), so g(a) = 3a -3 + |a + 3|

Set that expression equal to 2a + 8. Isolate the absolute value expression on one side, and keep in mind that |x| = x if x >= 0 and |x| = -x if x < 0.
 
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