פתרון
expand (x−x2)15
פתרון
x15−30x27+420x12−3640x21−96096x15−823680x9−2562560x3+21840x9+320320x6+1647360x3+3075072−x32795520+x31863680−x9860160+x6245760−x1532768
צעדי פתרון
(x−x2)15
(a+b)n=i=0∑n(in)a(n−i)bi :הפעל את הבינום של ניוטוןa=x,b=−x2
=i=0∑15(i15)x(15−i)(−x2)i
הרחב את הסכום
=0!(15−0)!15!x15(−x2)0+1!(15−1)!15!x14(−x2)1+2!(15−2)!15!x13(−x2)2+3!(15−3)!15!x12(−x2)3+4!(15−4)!15!x11(−x2)4+5!(15−5)!15!x10(−x2)5+6!(15−6)!15!x9(−x2)6+7!(15−7)!15!x8(−x2)7+8!(15−8)!15!x7(−x2)8+9!(15−9)!15!x6(−x2)9+10!(15−10)!15!x5(−x2)10+11!(15−11)!15!x4(−x2)11+12!(15−12)!15!x3(−x2)12+13!(15−13)!15!x2(−x2)13+14!(15−14)!15!x1(−x2)14+15!(15−15)!15!x0(−x2)15
0!(15−0)!15!x15(−x2)0פשט את:x15
1!(15−1)!15!x14(−x2)1פשט את:−30x227
2!(15−2)!15!x13(−x2)2פשט את:420x12
3!(15−3)!15!x12(−x2)3פשט את:−(x)33640x12
4!(15−4)!15!x11(−x2)4פשט את:21840x9
5!(15−5)!15!x10(−x2)5פשט את:−(x)596096x10
6!(15−6)!15!x9(−x2)6פשט את:320320x6
7!(15−7)!15!x8(−x2)7פשט את:−(x)7823680x8
8!(15−8)!15!x7(−x2)8פשט את:1647360x3
9!(15−9)!15!x6(−x2)9פשט את:−(x)92562560x6
10!(15−10)!15!x5(−x2)10פשט את:3075072
11!(15−11)!15!x4(−x2)11פשט את:−(x)112795520x4
12!(15−12)!15!x3(−x2)12פשט את:x31863680
13!(15−13)!15!x2(−x2)13פשט את:−(x)13860160x2
14!(15−14)!15!x1(−x2)14פשט את:x6245760
15!(15−15)!15!x0(−x2)15פשט את:−(x)1532768
=x15−30x227+420x12−(x)33640x12+21840x9−(x)596096x10+320320x6−(x)7823680x8+1647360x3−(x)92562560x6+3075072−(x)112795520x4+x31863680−(x)13860160x2+x6245760−(x)1532768
(x)33640x12=x3640x11
(x)596096x10=x96096x8
(x)7823680x8=x823680x5
(x)92562560x6=x2562560x2
(x)112795520x4=x232795520
(x)13860160x2=x29860160
(x)1532768=x21532768
=x15−30x227+420x12−x3640x11+21840x9−x96096x8+320320x6−x823680x5+1647360x3−x2562560x2+3075072−x232795520+x31863680−x29860160+x6245760−x21532768
x15−30x227+420x12−x3640x11+21840x9−x96096x8+320320x6−x823680x5+1647360x3−x2562560x2+3075072−x232795520+x31863680−x29860160+x6245760−x21532768אחד את:x15−30x227+420x12−104x23(35x9+924x6+7920x3+24640)+21840x9+320320x6+1647360x3+3075072−x232795520+x31863680−x29860160+x6245760−x21532768
=x15−30x227+420x12−104x23(35x9+924x6+7920x3+24640)+21840x9+320320x6+1647360x3+3075072−x232795520+x31863680−x29860160+x6245760−x21532768
−104x23(35x9+924x6+7920x3+24640)הרחב את:−3640x221−96096x215−823680x29−2562560x23
=x15−30x227+420x12−3640x221−96096x215−823680x29−2562560x23+21840x9+320320x6+1647360x3+3075072−x232795520+x31863680−x29860160+x6245760−x21532768
x15−30x227+420x12−3640x221−96096x215−823680x29−2562560x23+21840x9+320320x6+1647360x3+3075072−x232795520+x31863680−x29860160+x6245760−x21532768פשט את:x15−30x27+420x12−3640x21−96096x15−823680x9−2562560x3+21840x9+320320x6+1647360x3+3075072−x32795520+x31863680−x9860160+x6245760−x1532768
=x15−30x27+420x12−3640x21−96096x15−823680x9−2562560x3+21840x9+320320x6+1647360x3+3075072−x32795520+x31863680−x9860160+x6245760−x1532768