Prove x=nπ2 or x=(mπ2+3π8), where m, n∈I
sec22x=1−tan2x
⇒1+tan2 2x=1−tan2x
⇒tan22x+tan2x=0
⇒tan2x(tan2x+1)=0
⇒tan2x=0 or tan2x=−1
⇒2x=nπ or tan2x=−tanπ4=tan(π−π4)=tan3π4
⇒x=nπ2or2x=mπ+3π4, where m, n∈I
⇒x=nπ2orx=mπ2+3π8, where m, n∈I.
x=nπ+3π4 or x=mπ+tan−112, where m, n∈I
Prove x=nπ+(−1)n.π2 or x=(nπ+3π4), where m, n∈I
Prove x=(2nπ±2π3)orx=mπ+(−1)m.7π6, where m, n∈I
Prove x=(2nπ+π2) or x=2nπ, where n∈I.