Use the graphs of y fx and y gx to evaluate the function G
Solution
ANSWER Q. 80. See the value of y at -3, -2, 0 and 6 then look at the corresponding value of x. These are the values of f-1(x). The solution for f-1(x) are shown in table. below.
Directions: For problems 81 - 88 use the procedure discussed in Question No. 80.
ANSWER Q. 81. f-1(0) = 0.5 [See the graph of y = f(x) for the value of x at y=0]
ANSWER Q. 82. g-1(0) = -2 [See the graph of y = g(x) for the value of x at y=0]
ANSWER Q. 83. (fog)(2) = f [g(2)] = f(3) [Since, g(2)=3]
= -2 [From the graph of y=f(x)]
ANSWER Q. 84. g(f(-4)) = g (4) [Since, f(-4)=4]
= 6 [From the graph of y=g(x)]
ANSWER Q. 85. f-1(g(0)) = f-1 (2) [Since, g(0)=2]
= 0 [From the graph of y=f(x)]
ANSWER Q. 86. (g-1of)(3)) = g-1(f (3)) = g-1(-2) [Since, f(3)=-2]
= -3 [From the graph of y=g(x)]
ANSWER Q. 87. (gof-1)(2)) = g (f-1(2)) =g(0) [Since, f-1(2)=0]
= 2 [From the graph of y=g(x)]
ANSWER Q. 88. (f-1og-1)(-2)) = f-1(g-1 (-2) ) = f-1(-3) [Since, g-1(-2)=-3]
= 1 [From the graph of y=f(x)]
| x (for variable y) | f-1(x) |
| -3 | 4 |
| -2 | 3 |
| 0 | -1 |
| 6 | -2 |
