Since we know that x3 + y3 + z3 – 3xyz = (x + y + z)( x2 + y2 + z2 – xy – yz - zx)

Using (1) and (2) & x + y + z = 9

⇒ x3 + y3 + z3 – 3xyz = 81 × 9

∴ x3 + y3 + z3 – 3xyz = 729

Ace your Algebra preparations for Identities with us and master Quantitative Aptitude for your exams. Learn today!   Q1. The difference of two numbers is 5 và the difference of their squares is 105. Find the average of these numbers.

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Q2. The value of(frac3.57 imes 3.57 imes 3.57 - 1.23 imes 1.23 imes 1.233.57 imes 3.57 + 3.57 imes 1.23 + 1.23 imes 1.23)+ 2.56 will be:
Q5. If a + b - c = 0, then hat is the value of(frac(b-c)^24bcfrac(c-a)^24cafrac(a+b)^24ab?)
Q1. There were 120 students who went for summer camp. đôi mươi students joind them after some time, Due to lớn which the cost of consumption increased by Rs. 80 per day & the average cost of each students decrease by Rs. 5. Find the initial consumption of each student.
Q2. The difference of two numbers is 5 và the difference of their squares is 105. Find the average of these numbers.
Q3. The value of(frac3.57 imes 3.57 imes 3.57 - 1.23 imes 1.23 imes 1.233.57 imes 3.57 + 3.57 imes 1.23 + 1.23 imes 1.23)+ 2.56 will be:
Q8. If a + b - c = 0, then hat is the value of(frac(b-c)^24bcfrac(c-a)^24cafrac(a+b)^24ab?)  Admit CardExam PatternSyllabusCut OffResultsApplication StatusEligibility CriteriaAnswer KeyApply OnlinePrevious Year PapersPreparation TipsLatest UpdatesSalary Job ProfileExam AnalysisBooksTier 3 Descriptive PaperTier 2 Exam Analysis
Q1. If the incomes of Ram & Shyam are in the ratio of 3 ∶ 4 & their expenditures in the ratio of 4 ∶ 5,find the ratio of their savings, given that Shyam saves a third of his income.

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Q2. The average of 6 observations is 12. If the 7th observation is included, the average is reduced by 1. What will be the 7th observation?
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