Review questions: Logarithms TRUE or FALSE MATH 121
I. The exponential function bx = y
______ a. domain (x) is all Real Numbers
______ b. domain may include Z+, Z-, Q +, Q -, I+, I-
______ c. b is always > 0
______ d. Range (bx) is always > 0
______ e. If b > 1, graph looks like:
______ f. If b < 1, graph looks like:
______ g. If b < 0, graph looks like :
II. The logarithmic function Logbx = y
______ a. is the inverse of y = bx
______ b. domain (x) > 0
______ c. Range (y) is all reals
______ d. If graph of y = bx is
then graph of logbx = y is
______ e. b is always positive (usually > 1)
______ f. b ≠ 1
______ g. y = logbx is equivalent to by = x
III.
______ a. A log can be negative.
______ b. You can take the log of a negative number.
______ c. A log can be 0.
______ d. You can take the log of 0.
______ e. logbx - 1 = logb(x - 1)
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______ f. logb(x - 1) = logbx - logb1
______ g. logbx(1/2) = 1/2 logbx =
______ h. = logbx - logb2
______ i.
______ j. (logbx)3 = 3 logbx
______ k. (x - 1)log 3 = x log 3 - log 3
______ l. = 2
______ m. logbbn = n
______ n. = N
______ o. logb1 = 0
______ p. If 0 < N < 1, then log N < 0
______ q. logb(xb) = logbx + 1
______ r. If f is an exponential function and f(2) = , then f(x) = 3-x
______ s. If f is an exponential function and f(2) = , then b = -3
______ t. If log(1/3)x = -2, then log3 = -2