if a+b=7 and ab=12, then find the value of a 2 -ab+b 2 & a3-b3
Answers
Answered by
3
Answer:
(1)2
(2)-3
Step-by-step explanation:
(1)a2-ab+b2= 3*2-3*4+4*2=2
(2)a3-b3=3*3-4*3=9-12=-3
Answered by
2
Answer:
Step-by-step explanation:
a+b= 7
(a+b)^2= 49
a^2 + ab +b^2= 49
a^2 + 12 + b^2= 49
a^2 + 12 - 24 + b^2= 49-24
a^2 - 12 + b^2= 25
a^2 - ab + b^2 = 25
---------------------------------------------------
a^3 - b^3= (a – b) (a2 + ab + b2 )
a^3 - b^3= (a-b)49...….( I COULD DO THIS MUCH)
Similar questions