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 2 years ago
tan^2(60) + 4cos^2(45)  9tan^2(30)  8sin^2(30)
The answer is zero but why!? i need step by step solution please
 2 years ago
tan^2(60) + 4cos^2(45)  9tan^2(30)  8sin^2(30) The answer is zero but why!? i need step by step solution please

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Shadowys
 2 years ago
Best ResponseYou've already chosen the best response.0why can't you just plug the whole thing into your calculator?

CEBS95
 2 years ago
Best ResponseYou've already chosen the best response.0because in the exam they already give you the answer, you have to do the procedure

Callisto
 2 years ago
Best ResponseYou've already chosen the best response.2tan60 = \(\sqrt{3}\) cos45 = \(\frac{1}{\sqrt2}\) tan30 = \(\frac{1}{\sqrt3}\) sin30 = 1/2 These are all special angles and you should remember them.

CEBS95
 2 years ago
Best ResponseYou've already chosen the best response.0yes i know them but i just continue to get 6 instead of 0

Shadowys
 2 years ago
Best ResponseYou've already chosen the best response.0I'm getting zero just fine though. note the squares.

CEBS95
 2 years ago
Best ResponseYou've already chosen the best response.0tan^2(60) = 3 ? 4cos^2(45) = 4 ?

Callisto
 2 years ago
Best ResponseYou've already chosen the best response.24cos^2(45) = 4 (1/2) = ...?

CEBS95
 2 years ago
Best ResponseYou've already chosen the best response.0my math base is not good, that's the reason i wrote step by step solution

Callisto
 2 years ago
Best ResponseYou've already chosen the best response.2\[cos45 =\frac{1}{\sqrt2}\]\[cos^245 =(\frac{1}{\sqrt2})^2 = \frac{1}{2}\]\[4cos45 =4(\frac{1}{2}) = ...?\]

winterfez
 2 years ago
Best ResponseYou've already chosen the best response.0\[\frac{ \sin ^{2} (60)}{ \cos ^{2}(60)}+4\cos ^{2}(45)9\frac{ \sin ^{2}(30) }{ \cos ^{2}(30) }8\sin ^{2}(30)\]

winterfez
 2 years ago
Best ResponseYou've already chosen the best response.0dw:1355048071288:dw

CEBS95
 2 years ago
Best ResponseYou've already chosen the best response.0i found in my book that cos 45 = \[\frac{ \sqrt{2} }{ 2}\]

Callisto
 2 years ago
Best ResponseYou've already chosen the best response.2\[\frac{1}{\sqrt2}=\frac{1}{\sqrt2}\times \frac{\sqrt2}{\sqrt2}=\frac{\sqrt2}{\sqrt2^2} = \frac{\sqrt2}{2}\] Just rationalization.

CEBS95
 2 years ago
Best ResponseYou've already chosen the best response.09tan^2(30) = \[\tan( 30) = \frac{ \sqrt{3} }{ 3 } ; \tan ^{2}(30) = 3/9 = 1/3 \]

CEBS95
 2 years ago
Best ResponseYou've already chosen the best response.09tan^2(30)  8sin^2(30) = 3  8 = 5, at the end that will give me 5 (5) that equals 10

Callisto
 2 years ago
Best ResponseYou've already chosen the best response.28 sin ^2 (30) = 8 (1/2)^2 = 8 (1/4) = ...

winterfez
 2 years ago
Best ResponseYou've already chosen the best response.0dw:1355049445375:dw look at this one to see how i get 0

Callisto
 2 years ago
Best ResponseYou've already chosen the best response.2tan^2(60) + 4cos^2(45)  9tan^2(30)  8sin^2(30) tan^2(60) = \(\sqrt3^2\) = ... 4cos^2(45) = 4\((\frac{1}{\sqrt2})^2\) = 4(1/2) = ...  9tan^2(30) = 9 \((\frac{1}{\sqrt3})^2\) = 9 (1/3) = ...  8sin^2(30) = 8 (1/2)^2 = 8 (1/4) = ... Sum up the four answers.

winterfez
 2 years ago
Best ResponseYou've already chosen the best response.0dw:1355049643294:dw

CEBS95
 2 years ago
Best ResponseYou've already chosen the best response.0zero! nice thanks calisto

Callisto
 2 years ago
Best ResponseYou've already chosen the best response.2 30  45  60  sin  \(\frac{1}{2}\)  \(\frac{1}{\sqrt2} /\frac{\sqrt2}{2} \)  \(\frac{\sqrt3}{2}\)  cos  \(\frac{\sqrt3}{2}\)  \(\frac{1}{\sqrt2} /\frac{\sqrt2}{2} \)  \(\frac{1}{2}\)  tan  \(\frac{1}{\sqrt3} /\frac{\sqrt3}{3} \)  1  \(\sqrt{3}\)

CEBS95
 2 years ago
Best ResponseYou've already chosen the best response.0yes, with practice i will memorise the terms
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