А) 4y-1-2y+7+3y-1 5y+5 5(y+1)
--------------------- = -----------= --------- =
5y 5y 5y
y+1 y 1
----- = ----+ -----= y+1
y y y
л) 2×(a-b)×(a+b) 2a+6b 2×(a-b)
------------------- × -----------= ---------- =
2×(a+3b) b(a+b) b
2a-2b 2a 2b 2a
----------= ------ - ----- = ---- - b
b b b b
На фото........................................................................
task/29424356 ---------------------
49b²+14b +1 =(7b)² +2*7b*1 +1²= (7b+1)² * * * (7b+1) (7b+1) * * * --- uz⁶ +uy⁶ - yz⁶ - y⁷ =u(z⁶ +y⁶) - z(z⁶ +y⁶) = (u- z)(z⁶ + y⁶) .