Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 9 Answered

17. If a + b + c = 4 and a ^ 2 + b ^ 2 + c ^ 2 = 55/2 then find the value of a ^ 3 + b ^ 3 + c ^ 3 - 3abc
Asked by dalalvansh4 | 02 Jun, 2022, 07:03: PM
Expert Answer
open parentheses straight a plus straight b plus straight c close parentheses squared equals straight a squared plus straight b squared plus straight c squared plus 2 open parentheses ab plus bc plus ca close parentheses 4 squared equals 55 over 2 plus 2 open parentheses ab plus bc plus ca close parentheses rightwards double arrow 2 left parenthesis ab plus bc plus ca right parenthesis equals 16 minus 55 over 2 equals fraction numerator 32 minus 55 over denominator 2 end fraction equals negative 23 over 2 rightwards double arrow ab plus bc plus ca equals negative 23 over 4 open parentheses straight a cubed plus straight b cubed plus straight c cubed close parentheses minus 3 abc equals open parentheses straight a squared plus straight b squared plus straight c squared minus ab minus bc minus ca close parentheses open parentheses straight a plus straight b plus straight c close parentheses equals open parentheses 55 over 2 plus 23 over 4 close parentheses open parentheses 4 close parentheses equals open parentheses fraction numerator 110 plus 23 over denominator 4 end fraction close parentheses 4 equals 133
Answered by Renu Varma | 06 Jun, 2022, 11:00: AM

Concept Videos

Multiple Choice Questions Practice Test Subjective Questions Webinar Subjective Questions Pre Board Assessment
Answered Unanswered My Questions My Answers
CBSE 9 - Maths
factorise: a^7+ab^6
Asked by shivalaxmi0205 | 23 Feb, 2023, 10:28: PM
ANSWERED BY EXPERT
CBSE 9 - Maths
if x-2y=11 and xy=8. find the value of x³-8y³
Asked by shivalaxmi0205 | 21 Feb, 2023, 07:34: PM
ANSWERED BY EXPERT
CBSE 9 - Maths
if x-1/x=3, then find value of x³-1/x³.
Asked by shivalaxmi0205 | 21 Feb, 2023, 07:33: PM
ANSWERED BY EXPERT
CBSE 9 - Maths
(a+b+c)^3
Asked by kbalanbiju | 18 Jan, 2023, 07:16: PM
ANSWERED BY EXPERT
CBSE 9 - Maths
(3x-5y+4)(9x^2+25y^2+15xy-20y+12x+16)
Asked by mmansingh949 | 21 Jun, 2022, 09:54: AM
ANSWERED BY EXPERT
CBSE 9 - Maths
solve please
Asked by iamsimanta123 | 09 Jun, 2022, 07:30: AM
ANSWERED BY EXPERT
CBSE 9 - Maths
17. If a + b + c = 4 and a ^ 2 + b ^ 2 + c ^ 2 = 55/2 then find the value of a ^ 3 + b ^ 3 + c ^ 3 - 3abc
Asked by dalalvansh4 | 02 Jun, 2022, 07:03: PM
ANSWERED BY EXPERT
CBSE 9 - Maths
factorise the following a^3+b^3+3a-3b
Asked by s1044kasturipriyambada026582 | 27 May, 2022, 12:02: PM
ANSWERED BY EXPERT
CBSE 9 - Maths
I want to solve this question
Asked by abilash8b | 06 Jan, 2022, 12:27: PM
ANSWERED BY EXPERT
CBSE 9 - Maths
factorise 125x^3+27y^3
Asked by chintanasati.04ff2 | 13 Jul, 2021, 05:01: PM
ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt