Question

Please help me in this question​

Answer 1

Answer:

$( {2}^{ - 7} \times {2}^{ - 10} ) \div {2}^{ - 5}$

bases are equal powers must be added

$( {2}^{ - 7 - 10} ) \div {2}^{ - 5 } \\ {2}^{ - 17} \div {2}^{ - 5} \\ {2}^{ - 17 + 5} \\ = {2}^{ - 12 } \\ or \\ = 1 \div {2}^{ 12 }$