Вправа 401 - 500 » 458

458. Спрости вираз. а) 0,5х–6y2 • 4х7y–2 = 2ху0 = 2х; б) 8а–2b3 • 0,25а5b–1 = 2а3b2; в) 9а6b–2 : (–3а2b–5) = –За4b3. г) 〖12x〗^2/〖7y〗^7 • 〖14y〗^9/〖3x〗^(-2) = 4 • 2 • x4y2 = 8x4y2; ґ) (〖16a〗^4 b^6)/c^7 : (〖8b〗^6 c^(-6))/〖3a〗^(-2) = (〖16a〗^4 b^6 • 〖3a〗^(-2))/(c^7 • 〖8b〗^6 c^(-6) ) = 2a2 • 3 • c–1 = 6a2c–1; д) ((a^(-3) b^4)/5) • (10/(a^(-2) b^3 ))–3 = (a^(-3) b^4)/5 • 10^(-3)/(a^6 b^(-9) ) = (b^4 • b^9)/(a^3 •5 • 10^3 a^6 ) = b^13/〖5000a〗^9 ; е) 4a7c–1 • (ac/5)–1 = 4a7c–1 • 5/ac = (4 • 5 • a^7)/(ac^2 ) = 〖20a〗^6/c^2 ; є) a^(-2)/〖9c〗^2 : (〖3a〗^2/c^(-2) )–3 = 1/(〖9a〗^2 c^2 ) : (c^(-2)/〖3a〗^2 )3 = 1/(〖9a〗^2 c^2 ) : c^(-6)/〖27a〗^6 = 〖27a〗^6/(〖9a〗^2 c^2 c^(-6) ) = 〖3a〗^4/c^(-4) = 3a4c4;