Welcome :: Homework Help and Answers :: Mathskey.com
Welcome to Mathskey.com Question & Answers Community. Ask any math/science homework question and receive answers from other members of the community.

13,459 questions

17,854 answers

1,446 comments

808,056 users

Expand completely.

0 votes
Expand completely.
11) (2m − 1)^4
12) (x − y)^3
13) (x^4 − y)^5
14) (2x^3 + 1)^5
15) (y − x^2)^3
16) (y^3 − 4x)^3
asked Oct 26, 2018 in ALGEBRA 2 by anonymous

1 Answer

0 votes
11)
(2m − 1)^4  =  [ (2m − 1)^2 ] X [(2m − 1)^2 ]
                   =  [ 4m^2 - 4m + 1 ] X [ 4m^2 - 4m + 1 ]
                   =  (4m^2)(4m^2 - 4m + 1) - 4m(4m^2 - 4m + 1) + 1(4m^2 - 4m + 1)
                   =  (16m^4 - 16m^3 + 4m^2) - (16m^3 - 16m^2 + 4m) + (4m^2 - 4m + 1)
                   =  16m^4 - 16m^3 + 4m^2 - 16m^3 + 16m^2 - 4m + 4m^2 - 4m + 1
                   =   16m^4 - 32m^3 + 24m^2 - 8m + 1
 
12)
(x − y)^3  =  x^3 - 3(x^2)y + 3xy^2 - y^3
 
13)
(x^4 − y)^5  =  [ (x^4 − y)^2 ] X [ (x^4 − y)^3 ]  
                   =  [ (x^8 − 2(x^4)y + y^2 ] X [ x^12 -3(x^8)y + 3(x^4)y^2 - y^3 ] 
 
                   =  x^8[ x^12 -3(x^8)y + 3(x^4)y^2 - y^3 ]− 2(x^4)y[ x^12 -3(x^8)y + 3(x^4)y^2 - y^3 ]+ (y^2)[ x^12 -3(x^8)y + 3(x^4)y^2 - y^3 ] 
 
                   =  [ x^20 -3(x^16)y + 3(x^12)y^2 - (x^8)y^3 ] − [ 2(x^16)y -6(x^12)y^2 + 6(x^8)y^3 - 2(x^4)y^4 ] + [ (x^12)y^2 -3(x^8)y^3 + 3(x^4)y^4 - y^5 ] 
 
                   =  x^20 -3(x^16)y + 3(x^12)y^2 - (x^8)y^3 − 2(x^16)y + 6(x^12)y^2 - 6(x^8)y^3 + 2(x^4)y^4 + (x^12)y^2 -3(x^8)y^3 + 3(x^4)y^4 - y^5 
 
                   =  x^20 - 5(x^16)y + 10(x^12)y^2 - 10(x^8)y^3 + 5(x^4)y^4 - y^5 
 
14)
(2x^3 + 1)^5  = [ (2x^3 + 1)^2 ] X [ (2x^3 + 1)^3 ]
                      = [ 4x^6 + 4x^3 + 1 ] X [ (8x^9 + 12x^6 + 6x^3 + 1) ]
 
                      = 4x^6(8x^9 + 12x^6 + 6x^3 + 1) + 4x^3(8x^9 + 12x^6 + 6x^3 + 1) + 1(8x^9 + 12x^6 + 6x^3 + 1)
 
                      = 32x^15 + 48x^12 + 24x^9 + 4x^6 + 32x^12 + 48x^9 + 24x^6 + 4x^3 + 8x^9 + 12x^6 + 6x^3 + 1
 
                      = 32x^15 + 80x^12 + 80x^9 + 40x^6 + 10x^3 + 1
    
15)
(y − x^2)^3  =  y^3 -3(y^2)x^2 + 3yx^4 - x^6
 
16)
(y^3 − 4x)^3  =  y^9 - 3(y^6)(4x) + 3(y^3)(16x^2) - (4x)^3
                     =  y^9 - 12(y^6)x + 48(y^3)x^2 - 64x^3
 
Answer :
11) (2m − 1)^4  =  16m^4 - 32m^3 + 24m^2 - 8m + 1
12) (x − y)^3  =  x^3 - 3(x^2)y + 3xy^2 - y^3
13) (x^4 − y)^5  =  x^20 - 5(x^16)y + 10(x^12)y^2 - 10(x^8)y^3 + 5(x^4)y^4 - y^5 
14) (2x^3 + 1)^5   = 32x^15 + 80x^12 + 80x^9 + 40x^6 + 10x^3 + 1
15) (y − x^2)^3  =  y^3 -3(y^2)x^2 + 3yx^4 - x^6
16) (y^3 − 4x)^3   =  y^9 - 12(y^6)x + 48(y^3)x^2 - 64x^3.

 

answered Oct 27, 2018 by homeworkhelp Mentor
reshown Jun 1 by bradely

Related questions

asked Oct 26, 2018 in ALGEBRA 2 by anonymous
asked Dec 5, 2014 in ALGEBRA 2 by anonymous
asked Dec 5, 2014 in ALGEBRA 2 by anonymous
asked Jul 12, 2014 in ALGEBRA 2 by anonymous
asked Aug 8, 2014 in ALGEBRA 2 by anonymous
asked Jul 5, 2014 in ALGEBRA 2 by anonymous
...