Алгебра, 8 класс Упростите пожалуйста: 1) cd+2b+bd+2c 2) x+ay+ax+y 3) ax+y+ay+x 4) 3x+ax+3y+ay 5) x-y-ax-ay 6) x^2-y^4 7) -a^2+1 8) z^2-x^2*y^2 9) 9a^2-1/25b^2 10) x^8-1

1) cd+2b+bd+2c = cd+2c + 2b+bd = c(d+2)+b(d+2)= (c+b)(d+2) -------------------------------------------------------------------------------- 2) x+ay+ax+y = x+ax + ay+y = x(a+1) + y(a+1) = (1+a)(a+1) -------------------------------------------------------------------------------- 3) ax+y+ay+x = ax+x + y+ay = x(a+1) + y(a+1) = (x+y)(a+1) -------------------------------------------------------------------------------- 4) 3x+ax+3y+ay = x(3+a) + y(3+a) = (x+y)(3+a) --------------------------------------------------------------------------------- 5) x-y-ax-ay = x-ax - y-ay = x(1-a) - y(1+a) = (x-y) (1-a^2) ---------------------------------------------------------------------------------- 6) x^2-y^4 = (x-y^2)(x+y^2) -------------------------------------------------------------------------------- 7) -a^2+1 = -(a^2-1) = -(a-1)(a+1) ----------------------------------------------------------------------------------- 8) z^2-x^2*y^2=(z-xy)(z+xy) ------------------------------------------------------------------------------ 9) 9a^2-1/25b^2 = (3a-1/5b)(3a+1/5b) ------------------------------------------------------------------------------------ 10) x^8-1= (x^4-1)(x^4+1) ==================================================