1. The graph of y = h(x) is shown in red below. Compute h(h(7)).
(Assume grid lines are spaced 1 unit apart.)
2. Below is a portion of the graph of a function, y=u(x):
What is the exact value of u(-2.72)+u(-0.81)+u(0.81)+u(2.72) ?
+129847 1. h(7) means that we go to 7 on x and look at the y value at that point...this is 5
So h(7) = 5
So...now we are trying to find h(h(7)) = h(5)
So now...we do the same thing.....go to 5 on x and find the y value at that point = this is -1
So h(h(7)) = h(5) = -1 !!!
+129847 2. This one seems harder than it really is
This function is odd [ it is symmetric about the orgin ] which means that if ( - a, - b) is on the graph....then so is (a, b)
So u (-2.72) leads to some - b
And u (2.72) leads to some b
So adding these together, we get -b + b = 0
The same logic will apply to u(-0.81) and u(0.81)
Adding their outputs will = 0
So
u(-2.72)+u(-0.81)+u(0.81)+u(2.72) = 0
