Question

Раскройте скобки a+(b+c+d-c-f)
a-(-b-c-d+c-f)
a-(-b+c-d+c-f)
a+(b-c-d+d-c+f)

Answer 1

A+b+c+d-c-f
a+b+c+d-c+f
a+b-c+d-c+f
a+b-c-d+d-c+f

Answer 2

$a + (b + c + d - c - f) = a + b + c + d - c - f = a + b + d - f$

$a - ( - b - c - d + c - f) = a + b + c + d - c + f = a + b + d - f$

$a - ( - b + c - d + c - f) = a + b - c + d - c + f = a + b - 2c + f$

$a + (b - c - d + d \: - c + f) = a + b - c - d + d - c + f = a + b - 2c + f$