Question

Prove 1+tan^{​​​​2}​​​A=sec​​​​^​2​​​A

Answer 1

xplanation:

Starting from:

cos2(x)+sin2(x)=1

Divide both sides by cos2(x) to get:

cos2(x)cos2(x)+sin2(x)cos2(x)=1cos2(x)

which simplifies to:

1+tan2(x)=sec2(x)