sigridhans

Thanks a lot. Sadly, I have forgotten most of my highschool math and I haven't learned to code yet. I tried already with CAS but the program keeps telling me that I need to specify and gives me another equation as the solution. Below are the steps I did for the year 1990. Is it wrong so far? Can I somehow isolate x in the equation below and specify that the answer is between a and 365? Kind regards,

Hello, I am modelling the length of the growth season for 120 different years based on estimated daily temperature. The temperature is estimated from a periodic function: f(x)=D+A*sin(B(x+C), where the constants B and C are the same every year and A and D varies. So I would like to know when the area under each function equals 1200 as shown in the figure. I think it can be solved by finding the upper limit b in equation 1 when the lower limit a is known. For the year 1990 it would look like equation 2, and b will take a value between a and 365. Do you know how I can calculate this using Excel? Thanks in advance,