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Help, I don’t know what I’m doing
Trigonometry

Help, I don’t know what I’m doing Trigonometry-example-1
User Jalperin
by
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2 Answers

14 votes
14 votes

The answer is
\boxed {(1)/(2√(3))}

The needed trigonometric values :

  • The value of cot 60° = 1/√3
  • The value of cos 60° = 1/2

Hence, the value of the expression is :

  • cot 60° × cos 60°
  • 1/√3 × 1/2
  • 1/2√3
User Mark Pavlis
by
2.1k points
23 votes
23 votes

Answer:


(√(3) )/(6)

Explanation:

using the 30- 60- 90 triangle for exact values , then

tan60° =
√(3) , and

cot60° =
(1)/(tan60) =
(1)/(√(3) )

cos60° =
(1)/(2)

cot60° cos60°

=
(1)/(√(3) ) ×
(1)/(2)

=
(1)/(2√(3) ) ← rationalise the denominator by multiplying by
(√(3) )/(√(3) )

=
(1)/(2√(3) ) ×
(√(3) )/(√(3) )

=
(√(3) )/(6)

User Linuts
by
3.2k points