Question

Степени 7 класс алгебра ​

Answer 1

$№1$

${x}^{12} \div {x}^{5} = {x}^{12 - 5} = {x}^{7}$

${a}^{14} \div {a}^{8} = {a}^{14 - 8} = {a}^{6}$

$(2xy)^{3} = {2}^{3} {x}^{3} {y}^{3} = 8 {x}^{3} {y}^{3}$

$(3mk)^{4} = {3}^{4} {m}^{4} {k}^{4} = 81{m}^{4} {k}^{4}$

$№2$

$- 4bc^{5} \times 5 {b}^{4} {c}^{2} = - 20 {b}^{1 + 4} {c}^{5 + 2} = - 20 {b}^{5} {c}^{7}$

$8x^{2} y \times ( - 1.5 {y}^{2} {x}^{3} ) = - 12 {x}^{2 + 3} {y}^{1 + 2} = - 12 {x}^{5} {y}^{3}$

$( - 2xy^{3} )^{5} = ( - 2)^{5} {x}^{5} {y}^{3 \times 5} = - 32 {x}^{5} y ^{15}$

$№3$

$\frac{( {2}^{6})^{3} \div 2 }{({2}^{3})^{2} \times {2}^{2} } = \frac{ {2}^{6 \times 3} \div 2 }{ {2}^{3 \times 2} \times {2}^{2} } = \frac{ {2}^{18} \div 2}{ {2}^{6} \times 2^{2} } = \frac{ {2}^{18 - 1} }{ {2}^{6 + 2} } = \frac{ {2}^{17} }{ {2}^{8} } = {2}^{17 - 8} = 2 ^{9} = 512$

$(0.5 \times {4}^{2} - 11) ^{3} = (0.5 \times 16 - 11)^{3} = (8 - 11)^{3} = ( - 3)^{3} = - 27$