Question

1)sin^2α+1/cos^2α-1+tg*ctg
2)sin(π/2+α)tg(π-α)/cos(3/2π-α)ctg(π+α)

Answer 1

1)(sin²α+1)/(cos²α-1)+tgα*ctgα=(sin²α+1)/(-sin²α)+1=-1-(1/(sin²α))+1=-(1/(sin²α))

2)sin(π/2+α)tg(π-α)/cos(3/2π-α)ctg(π+α)=cosα*(-tgα) /(-sinα)ctgα=

sinα/cosα=tgα