If a^2+b^2=39 and ab=18
Find the value of a^4-2a^2b^2=b^4
Please give the complete step
F.3Maths (Factorization)
2010-09-09 4:32 am
回答 (1)
2010-09-09 4:36 am
✔ 最佳答案
If a^2+b^2=39 and ab=18Find the value of a^4-2a^2b^2+b^4 <==corrected
a^4-2a^2b^2+b^4
= a^4 + 2a^2 b^2 + b^4 - 4a^2 b^2
= (a^2 + b^2)^2 - 4(ab)^2
= 39^2 - 4(18)^2
= 39^2 - (36)^2
= (39-36)(39+36)
= 3(75)
= 225
參考: Hope the solution can help you^^”
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