Cobwebbing is a graphical approach to finding and visualizing sequences a0, a1, a2, . . . that are solutions of a difference equation (recurrence relation) an = f(an-1). In the script below, enter f(t) and a0. When entering f(t), you can use +, -, *, /, ^, ( ), abs(), sin(), cos(), tan(), exp(), log(), log10(), asin(), acos(), atan(), pi, e. Take care to remember the * in all multiplications. Also, note that here, log() stands for the natural logarithm, while log10() stands for the common logarithm. When entering a0, you can use integers and decimals. Press the "Enter" button. Then repeatedly (at most 20 times) press the "Step" button to move from the output y = an-1 to the input x = an-1 by reflectiong across the line y = x, and then move to the output y = an.
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