Question

2 tan 30 Ittan²3
$(7x \times )3654y$
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Answer 1

Answer: cos 30

Step-by-step explanation:

tan 30 = 1/√3

then 2tan30/(1+tan^2 30) is= 2×1/√3 / (1+(1/√3)²)

= 2/√3 / (1+1/3)         in brackets by taking 3 as lcm we get

= 2/√3 / (3+1/3)

= 2/√3 / 4/3

= 2/√3×3/4

= 3 / 2√3   (3 can be written as √3×√3)

= √3×√3 / 2√3

= √3/2

= cos 30