Let fx 2x2 3x 1 and h x 2 x2 3 x 1 The graph of h can
Let f(x) = 2x^2 + 3x + 1 and h (x) = 2 (-x)^2 + 3 (-x) + 1. The graph of h can be derived from the graph of f by: Shifting the graph of f to the left one unit Shifting the graph of f down one unit Reflecting the graph of f across the x-axis Reflecting the graph of f across the y-axis None of these Let f(x) = 2x^2 + 3x + 1 and h (x) = 2(-x)^2 + 3(-x) + 1. The graph of h can be derived from the graph of f by; Shifting the graph of f to the left one unit Shifting the graph of f down one unit Reflecting the graph of f a across the x-axis Reflecting the graph of f across the y-axis None of these Let f (x) = 5x^4 - 7x + 1 and g(x) = 5x^4 +7x + 1. The graph of g can be derived from the graph of f by: Reflecting the graph of f across the x-axis Reflecting the graph of f across the y-axis Reflecting the graph of f across the x-axis first then across the y-axis None of the above Let f(x) = 3x^4 - 7x^2 + 1. Find the function that is the reflection of f(x) about y-axis.
Solution
5] f(x) = 2x2 + 3x + 1 and g(x) = 2(- x)2 + 3(-x) + 1
from g(x), we see that x has been replaced by \' - x\'
so, the graph will be reflected about the y-axis.
6] f(x) = 5x4 - 7x + 1 and g(x) = 5x4 + 7x + 1
since ( - x)4 = x4, we can rewrite g(x) as: g(x) = 5( - x)4 - 7( - x) + 1
which is identical to f(x) but x has been replaced by \' - x\'
therefore g(x) is a reflection of f(x) about y axis.
7] f(x) = 3x4 - 7x2 + 1
if a function is a reflection about y axis, g(x) = 3( - x)4 - 7(- x)2 + 1 = 3x4 - 7x2 + 1 = f(x).
