Name: Anonymous 2007-11-19 15:56
I need help with a question, I've done most of it.
"Given that y=e^-x sin2x, show that dy/dx can be expressed in the form R e^-x cos(2x + α). Find, to 3 significant figures, the values of R and α, where 0 < α < π/2."
I got the differentiated part to "-e^-x sin2x + 2e^-x cos2x" which is where i begin to use the harmonic form.
I also got α = to 26.6° but finding R is a real pain. Mainly because I can't get rid of the "x" power.
Can anyone help?
"Given that y=e^-x sin2x, show that dy/dx can be expressed in the form R e^-x cos(2x + α). Find, to 3 significant figures, the values of R and α, where 0 < α < π/2."
I got the differentiated part to "-e^-x sin2x + 2e^-x cos2x" which is where i begin to use the harmonic form.
I also got α = to 26.6° but finding R is a real pain. Mainly because I can't get rid of the "x" power.
Can anyone help?