1.

1). 02). 13). 24). √3/2

Answer»

tan70° tan20° + SIN280° + sin2 10°

we KNOW that, TAN (π/2 – θ) = cot θ

also, sin (π/2 – θ) = cos θ

∴ tan70° tan20° + sin280° + cos210°

= tan (π/2 – 20°) tan 20° + sin2(π/2 – 10°) + sin210°

= cot20° tan20° + (cos210° + sin210°)(? cotθ tanθ = 1 and cos2θ + sin2θ = 1)

= 1 + 1 = 2



Discussion

No Comment Found