Bonjour ;
Exercice n° 2 .
[tex]A = a^{-3} \times a^{-20} = a^{-3-20} = a^{-23} .[/tex]
[tex]B = a^{13} \times a^{-2} \times a^{-21} = a^{13-2-21} = a^{13-23} = a^{-10} .[/tex]
[tex]C = \dfrac{ a^{-5} }{a^{7} } = a^{-5} \times a^{-7} = a^{-5-7} = a^{-12} .[/tex]
[tex]D = \dfrac{ a^{-25} }{ a^{-17} } = a^{-25-(-17)} = a^{-25+17} = a^{-8} .[/tex]
[tex]E = ( a^{-3} )^{15} = a^{-3 \times 15} = a^{-45} .[/tex]
[tex]F = (a^{-10})^{-5} = a^{-10 \times (-5)} = a^{50} .[/tex]
