In part b), it is supposed to be a period, not a multiplication. They are using as the value of you found in part a). So, if , then . Now, replace with since they are equal by assumption. So, . Next, substitute in the value set for : .
I understand part a) as the equation is worked so that it is in terms of k. The solution for part b) is losing me at:
I see that where t was before there is now the symbol lambda but the part after the * symbol is lost on me right now. Why is the equation in terms of k now being multiplied by:
Thanks for any responses...
In part b), it is supposed to be a period, not a multiplication. They are using as the value of you found in part a). So, if , then . Now, replace with since they are equal by assumption. So, . Next, substitute in the value set for : .
Hey sepoto.
Remember that you are looking at the time t1 + lambda and not t1 (and you also have the information about the half life at t1 and t1 + lambda from the question). Just plug in the information for the lambda + t1 and everything should be ok.