hi i am really struggling with these 2 questions and any help would be deeply appreciated.
1. 2cos 2theta= 7 sintheta solve for 0<theta<2 pi, answer to one decimal
2. prove that
1 - tan squared theta / 1 + tan squared theta = cos 2 theata
thanks for that but im still really struggling to get the final answer.
for 1. i've got to 4sinsquared theta + 7 sin theta -2=0 do i then factorise or what.
2.ive mulitplied by cos squared theta and got
cos squared theta - sin squared theta / cos squared theta + sin squared theta. not sure what to do next