Question

Matemática

1) efetue como achar melhor.

A) (7-3c)²=

B) (5x-2y)²=

C)(2-x³)²=

D) (xy-10)²=

E)(x-0,2)²=

F)(-4x-3y)²=

Answer 1

$A)~(7-3c)^{2} =7^{2} -2.7.3c+(3c)^{2} =49-42c+9c^{2}$

$B)~(5x-2y)^{2} =(5x)^{2} -2.5x.2y+(2y)^{2} =25x^{2} -20xy+4y^{2}$

$C)~(2-x^{3})^{2} =2^{2} -2.2.x^{3} +(x^{3})^{2} =4-4x^{3} +x^{5}$

$D)~(xy-10)^{2} =(xy)^{2} -2.xy.10+10^{2} =x^{2} y^{2} -20xy+100$

$E)~(x-0,2)^{2}=x^{2} -2.x.0,2+0,2^{2} =x^{2} -0,4x+0,04$

$F)~(-4x-3y)^{2} =(-4x-3y)(-4x-3y)=(4x)^{2} +12xy+12xy+(3y)^{2} =\\ \\ 16x^{2} +24xy+9y^{2}$