Question

■■■■NEED HELP■■■■

The value of tan10° • tan20°• tan45°• tan70° • tan80°


(a) 1
(b) 1/√3
(c) 0
(d) 8




*EXPLAIN* your answer.

Answer 1

Hey

Ans is (a)
Using complementary angles tan10, and tan80 will be cancelled out and tan20 and tan70 will be canceled out.
Remaining tan 45=1
So the and is 1

Answer 2

Hello dear sister....!!

The answer is option (A).

According to the given question,

Tan 10 • Tan 20 • Tan 45 • Tan 70 • Tan 80 = ??????

Solution :


>Tan 10• Tan20• ( 1 ) • Tan ( 90 - 20 ) • Tan ( 90 - 10 )

>Tan 10 • Tan 20 • Cot 20 • Cot 10•(1)

> Tan 10 • Tan 20 • 1 / Tan 20 • 1 / Tan10 ( 1)

> ( 1 ) • ( 1 ) • ( 1 ) = 1

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Therefore

Tan 10 • Tan 20 • Tan 45 • Tan 70 • Tan 80 = 1 .

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Hope it is useful....!!!