f(x)=dx10d10((x2−1)10)
g(x)=(x2−1)10
Check: coeff of x8, f(1)+f(−1), degf, constant term
g(x)=∑k=010(k10)(−1)10−kx2k
[xm]f=am+10⋅m!(m+10)!
degg=20⇒degf=20−10=10
⇒(3) TRUE
a18=(910)(−1)1=−10
[x8]f=a18⋅8!18!=(−10)8!18!
⇒(1) TRUE
x=1+t: (x2−1)10=(2t+t2)10=t10(2+t)10
f(1)=10!210,f(−1)=10!210
⇒f(1)+f(−1)=10!211⇒(2) TRUE
a10=(510)(−1)5=−252
f(0)=10!⋅(−252)=−(5!10!)2
=−5!10!⇒(4) FALSE
TRUE: (1), (2), (3)