[tex] \displaystyle\\
a)\\
2-\frac{3}{4}=\frac{8}{4}-\frac{3}{4}=\boxed{\frac{5}{4}}\\\\
b)\\
\frac{2016}{2015}>1\\\text{deoarece numaratorul (2016) e mai mare decat numitorul (2015).}\\
\text{Spunem ca fractia este supraunitara.}\\\\
\frac{2016}{2017}<1\\\text{deoarece numaratorul (2016) e mai mic decat numitorul (2017).}\\
\text{Spunem ca fractia este subunitara.}\\\\
\Longrightarrow~\frac{2016}{2017}<1< \frac{2016}{2015}]\\\\
\Longrightarrow~\boxed{\frac{2016}{2015}~\text{este cea mai mica fractie.}} [/tex]
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[tex] \displaystyle\\
c)\\
\text{A-----------P------Q------B}\\\\
\text{P este mijlocul lui AB}\\\\
\Longrightarrow~~AP=PB=\frac{AB}{2}\\\\
\text{Q este mijlocul lui PB}\\\\
\Longrightarrow~~PQ=QB=\frac{PB}{2}=\frac{\dfrac{AB}{2}}{2}=\frac{AB}{4}\\\\
AQ = AB-QB = AB - \frac{AB}{4}=\frac{4AB-AB}{4}=\frac{3AB}{4}\\\\
AQ=4,\!5~cm\\\\
\frac{3AB}{4} = 4,\!5~cm\\\\
AB = 4,\!5 \cdot \frac{4}{3}=\frac{18}{3}=\boxed{\bf 6~cm}
[/tex]
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[tex] \displaystyle\\
d)\\
180^o-63^o 14' 36''=\\
=179^o60'-63^o 14' 36''=\\
=179^o59'60''-63^o 14' 36''= 116^o45'24''\\\\\\
e)\\
90 -x = \frac{1}{4} (180 - x)\\\\
90 -x = \frac{180 - x}{4} \\\\
4(90 -x)=180 - x\\\\
360 - 4x = 180 - x~~~\text{(Facem rocada.)}\\\\
180 - x = 360 - 4x\\\\
4x-x=360-180\\\\
3x = 180\\\\
x = \frac{180}{3}= \boxed{\bf 60^o} [/tex]
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