i need help solving this problem
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Answer:
[tex]3x^7{\cdot} (4x^{-5})^2=\dfrac{48}{x^3}[/tex]
Step-by-step explanation:
We need to simplify the given expression :
[tex]3x^7{\cdot} (4x^{-5})^2[/tex]
Use property : [tex]x^{-a}=\dfrac{1}{x^a}[/tex]
[tex]3x^7{\cdot} (\dfrac{4}{x^5})^2\\ =3x^7{\cdot} \dfrac{16}{x^{10}}\ \ [\because (x^a)^b=x^{a\times b}]\\\\=\dfrac{48}{x^3}[/tex]
So, the simplified form of the given expression is [tex]\dfrac{48}{x^3}[/tex]