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Which of the following is the expansion of (2m - n)7? 128m7 448m6n 672m5n2 560m4n3 280m3n4 84m2n5 14mn6 n7 128m7 14m6n 42m5n2 70m4n3 70m3n4 42m2n5 14mn6 n7 m7 7m6n 21m5n2 35m4n3 35m3n4 21m2n5 7mn6 n7 128m7 - 384m6n 480m5n2 - 320m4n3 160m3n4 - 60m2n5 12mn6 - n7 128m7 - 448m6n 672m5n2 - 560m4n3 280m3n4 - 84m2n5 14mn6 - n7

User Dmkvl
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1 Answer

2 votes

Answer:

The last one

Step-by-step explanation:

(2m - n) ^ 7 * c * a * n be expanded using the binomial theorem or pascal's triangle, but writing out the work is proving to be really difficult. the application of the theorem is pretty complicated and it isn't easy to format in this textbox.

the expansion of this would be 128m ^ 7 - 448m ^ 6 * n + 672m ^ 5 * n ^ 2 - 560m ^ 4 * n ^ 3 + 280m ^ 3 * n ^ 4 - 84m ^ 2 * n ^ 5 + 14m * n ^ 6 - n ^ 7.

hope this helped

User Jkupczak
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