sin4\3 π *cos 5\6 π * tan(-4\3π)

sin4\3 π *cos 5\6 π * tan(-4\3π)
sin4\3 π *cos 5\6 π * tan(-4\3π)

sin4\3 π *cos 5\6 π * tan(-4\3π)
=(-sinπ/4)(-cosπ/6)(-tanπ/3)
=-√2/2*√3/2*√3
=-3√2/4

1、m(x-2)-n(x-2)+p(2-x)
=m(x-2)-n(x-2)-p(x-2)
=(x-2)(m-n-p)
2、x^2y(x-y)^2-2xy(y-x)^3
=x^2y(x-y)^2+2xy(x-y)^3
=xy(x-y)^2[x+2(x-y)]
=xy(x-y)^2(3x-2y)
3、15(a-b)^2+6a(b-a)
=...

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1、m(x-2)-n(x-2)+p(2-x)
=m(x-2)-n(x-2)-p(x-2)
=(x-2)(m-n-p)
2、x^2y(x-y)^2-2xy(y-x)^3
=x^2y(x-y)^2+2xy(x-y)^3
=xy(x-y)^2[x+2(x-y)]
=xy(x-y)^2(3x-2y)
3、15(a-b)^2+6a(b-a)
=15(a-b)^2-6a(a-b)
=3(a-b)[5(a-b)-6a]
=-3(a-b)(a+5b)
4、(a+b-c)(a-b+c)+(b-a+c)(b-a-c)
=(a+b-c)(a-b+c)-(b-a+c)(a-b+c)
=(a-b+c)[(a+b-c)-(b-a+c)]
=2(a-b+c)(a-c)

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