The next guess for x, which will be x_2, will be the x-intercept of the line whose slope is the slope of the function at x_1.
a) The slope is positive on a portion of the graph that has a horizontal asymptote. Newton's method will give guesses that approach negative infinity.
b) The slope is zero. Newton's method will give a guess of infinity or "overflow" or "not a number" or "error" depending on how division by zero is treated. The tangent line is parallel to the x-axis, so there is no x-intercept.
c) It looks like the slope is negative, but will give a guess in the same region as for answer (a). (For guesses near 2, it is likely Newton's method would converge on the solution near x=2. The function is well-behaved in a small area there, so x_1 must be "close enough" for there to be convergence.)
d) The slope appears to be zero at x=4, so the answer is the same as for (b).
e) The iteration method will give guesses that are likely to converge to the solution near x=6.
