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$\small \left(\tan(30°)-\tan(60°)\right)\left(\cos(30°)+\sin(60°)\right)-\sin^2\left(45°\right) =$
$\small = \left(\dfrac{\sqrt3}{3}-\sqrt3\right)\left(\dfrac{\sqrt3}{2}+\dfrac{\sqrt3}{2}\right)-\left(\dfrac{\sqrt2}{2}\right)^2 =$
$\small = \dfrac{\cancel3^1}{\cancel6_2}+\dfrac{\cancel3^1}{\cancel6_2}-\dfrac{3}{2}-\dfrac{3}{2}-\dfrac{(\sqrt2)^2}{2^2} =$
$\small = \dfrac{1}{2}+\dfrac{1}{2}-\dfrac{\cancel6^3}{\cancel2_1}-\dfrac{\cancel2^1}{\cancel4_2} =$
$\small = \dfrac{1}{2}+\dfrac{1}{2}-3-\dfrac{1}{2} =$
$\small = \dfrac{1}{2}+\cancel{\dfrac{1}{2}}-3-\cancel{\dfrac{1}{2}} =$
$\small = \dfrac{1}{2}-3 =$
$\small = \dfrac{1-6}{2} =$
$\small = -\dfrac{5}{2} $
@gramor grazie milleeee non è che riusciresti a risolvermi anche quelli che ho caricato il numemero 4 e 6