please help me show the steps to prove cot(15°)=2+√3
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cot(15)=1/tan15
tan(45-30)
we know that tan(A-B)=tanA-tanB/1+tanAtanB
1-1/√3/1+1/√3
⇒√3-1/√3+1
on rationalization
√3 - 1 . √3-1
√3 +1 √3-1
3+1-2√3/3-1=4-2√3/2⇒2-√3
cot 15=1/tan 15=1/2-√3
again rationalize
1 .2+√3
2-√3 . 2-√3
⇒2+√3/4-3⇒2+√3
tan(45-30)
we know that tan(A-B)=tanA-tanB/1+tanAtanB
1-1/√3/1+1/√3
⇒√3-1/√3+1
on rationalization
√3 - 1 . √3-1
√3 +1 √3-1
3+1-2√3/3-1=4-2√3/2⇒2-√3
cot 15=1/tan 15=1/2-√3
again rationalize
1 .2+√3
2-√3 . 2-√3
⇒2+√3/4-3⇒2+√3
yiyi:
ok, wait a moment
okk
cot(15)=cos(15)/sin(15)
next
=sqrt6+sqrt2/4 x 4/sqrt6-sqrt2
come on chat box,there we can discuss this
okok
hmm
haha, where can i find the chatbox?sorry im new~XP
ohkk
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