Question

prove that tan48°,tan23°,tan42°,tan67°=1

Answer 1

Answer:

Step-by-step explanation:

Tan48=cot42

Tan23=cot67

Tan×cot×tan×cot=1

Hence proved

Answer 2

Solution :

LHS = tan48°tan23°tan42°tan67°

Rearranging the terms, we

get

= tan67°tan23°tan42°tan48°

= tan67°tan(90-67°)tan42tan(90-42)

= tan67°cot67°tan42°cot42°

= 1 × 1

= 1

= RHS

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