cosα(2secα+tanα)(secα-2tanα)+3tanα =cosα(2secα*secα-4secα*tanα+secα*tanα-2tanα*tanα)+3tanα =cosα[2(secα*secα-tanα*tanα)-4secα*tanα+secα*tanα]+3tanα =cosα(2-3secα*tanα)+3ta...