∵tanα=1/3∴sinα/cosα=1/3∴cosα=3sinα sin^2α+sinαcosα+2cos^2α=(sin^2α+sinαcosα+2cos^2α)/(sin²α+cos²α)=(sin²α+3sin²α+2*9sin²α)/(sin²α+9sin²α)=22si...