Latest Elitmus Aptitude Question SOLUTION: If a = tan6 tan 42 and B = cot66 cot 78 then (a) A = 2B (b) 1 AB 3 = (c) A = B (d) 3A = 2B.

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(#M40009744) ELITMUS Numerical Ability question Keep an EYE

If a = tan6 tan 42
and B = cot66 cot 78
then

(a) A = 2B (b)
1
AB
3
=
(c) A = B (d) 3A = 2B.

Asked In Elitmus pankaj prajapati (11 years ago)

Unsolved Read Solution (5)

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Read Solution (5) :

Srinvas Choudary  (11 years ago)

a=tan6 tan42
b=cot66 cot78 can be written as tan24 tan12 bec cot(90-t)=tant;
tanA tanB = tanC tanD if A+B=C+D; or A+B =C-D or A-B=C+D or A-B=C-D;
as 42-6=24+12;
both are equal.

Is this solution Helpfull? Yes (34) | No (5)  

Vignesh  (11 years ago)

c) A = B

If A = tan6 tan 42 and B = cot66 cot 78 then,

A/B = 1. So, A =B

Is this solution Helpfull? Yes (16) | No (7)  

Mukesh Kr Singh  (11 years ago)

value of tan6tan42=-0.67
and cot66cot78=-1.005
so,3A=2B is rd. answer

Is this solution Helpfull? Yes (4) | No (17)  

Amarpal Singh  (9 years ago)

We know that tanx*tan(60-x)*tan(60+x)=tan3x
now A/B=tan6.tan42.tan66.tan78

Is this solution Helpfull? Yes (1) | No   

sss  (6 years ago)

A=tan6°tan42° and B=cot66°cot78°
A/B=tan6°tan42°tan66°tan78°
Using tan(60-x)tanxtan(60+x)=tan3x for x=18° we get
tan42°tan18°tan78°=tan54°...(1)
for x=6° we get
tan54°tan6°tan66°=tan18°...(2)
Eliminating tan54°between (1) and (2)
we get
tan6°tan42°tan66°tan78°=1
Hence A/B=1.

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