Question

sec 70 degree sin 20 degree + cos 20 degree + cosec 70 degree =2​

Answer 1

To prove that :-

sec70° sin20° + cos20° + cosec70° = 2

----------------------

Solution :-

LHS :-

→ sec70° sin20° + cos20° + cosec70°

→ sec(90 - 20) x sin20 + cosec(90 - 20) + cos20

→ $\frac{1}{sin20}$ x sin20 + $\frac{1}{cos20}$ x cos20

→ 1 + 1

→ 2

→ RHS

Hence proved.

Answer 2

Answer:

→ 2(x − 1) + 5(x − 2) = 5x

→ 2x - 2 + 5x - 10 = 5x

→ 7x - 12 = 5x

→ 7x - 5x = 12

→ 2x = 12

→ x = 12/2

→ x = 6