Qs 18
a) Given that tanx = ktany
i ) Show that sin(x+y)=(k+1)cosxsiny.
ii)Hence, show that (k+1)sin(x-y)=(k-1)sin(x+y).
更新1:
also bii) and c, thz~ b) Given that tan(Θ+10°)= ktan(Θ-20°) has solution in Θ. i) Show that sin(2Θ-10°)= (k+1)/2(k-1). ii) Hence, find the range of possible values of k. c) Find the general solution of tan(Θ+10°)= -2tan(Θ-20°), correct the answer to nearest 0.1 degree.