## College Algebra (10th Edition)

$y=Cx(x+1)$
RECALL: For positive real numbers M and N: (1) $\ln{M} = \ln{N} \longrightarrow M=N$ (2) Product Rule: $\ln{M} + \ln{N} = \ln{(MN)}$ (3) Quotient Rule: $\ln{M} - \ln{N} = \ln{\left(\dfrac{M}{N}\right)}$ (4) Power Rule: $r\cdot ln {M} = \ln{(M^r)}$ Apply the Product Rule to the first two terms on the right side of the equation to obtain: $\ln{y}=\ln{x} + \ln{(x+1)}+\ln{C} \\\ln{y} = \ln{\left[x(x+1)\right]} +\ln{C}$ Apply the Product Rule again to obtain: $\ln{y}=\ln{x} + \ln{(x+1)}+\ln{C} \\\ln{y} = \ln{\left[x(x+1)(C)\right]} \\\ln{y} = \ln{\left[Cx(x+1)\right]}$ Use rule (1) above to obtain: $y=Cx(x+1)$