Respuesta :
Answer:
[tex]T_{9}=329472x^{5}y^8[/tex]
Step-by-step explanation:
[tex](x-2y)^{13}[/tex]
[tex]T_{r+1}=nCr x^{n-r} y^r[/tex]
x is the first term in the given parenthesis and y is the second tern
r= 8, r+1=9 because we need to find 9th term
x is x and y is 2y. n is the exponent 13. plug in all the values
[tex]T_{8+1}=13C8 x^{13-8} (2y)^8[/tex]
[tex]T_{8+1}=13C8 x^{5} (2y)^8[/tex]
nCr= [tex]\frac{n!}{r!(n-r)!}=\frac{13!}{8!(5!)=1287[/tex]
[tex]T_{8+1}=1287x^{5} 256y^8[/tex]
[tex]T_{9}=329472x^{5}y^8[/tex]
