Question 69

If $$x + y + z = 3 and xy + yz + zx = -18$$,then what is the value of $$x^3 + y^3 + z^3 - 3xyz = ?$$

Solution

Formula,

$$x^3 + y^3 + z^3 - 3xyz$$ = $$(x +y + z)*((x + y + z)^2 - 3(xy +yz +zx))$$

Put the required values , we get = 189

Create a FREE account and get:

Free SSC Study Material - 18000 Questions
230+ SSC previous papers with solutions PDF
100+ SSC Online Tests for Free

CAT Quant Questions | CAT Quantitative Ability

CAT Algebra Questions CAT Data Sufficiency Questions CAT Time, Distance and Work Questions CAT Number Systems Questions CAT Linear Equations Questions

CAT DILR Questions | LRDI Questions For CAT

CAT DI with connected data sets Questions CAT Routes And Networks Questions CAT Special Charts Questions CAT Table with Missing values Questions CAT Selection With Condition Questions

CAT Verbal Ability Questions | VARC Questions For CAT

CAT Vocabulary Questions CAT Miscellaneous Questions CAT Odd One Out Questions CAT Verbal Ability Questions CAT Critical Reasoning Questions

Follow us on

Boost your Prep!

Download App