if a+b+c =10 and ab+bc+ca=15 find (a+b+c)(a^2+b^2+c^2-ab-bc-ca)
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550 is the answer please mark as brainlist
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Hi ,
a + b + c = 10 ----( 1 )
ab + bc + ca = 15 ----( 2 )
2( ab + bc + can ) = 30 ---( 3 )
a² + b² + c² = ( a +b+c)²-2( ab+bc+ca)
= 10² - 30
= 70 --- ( 4 )
Now ,
( a +b+c)[a²+b²+c²-(ab+bc+ca)]
= 10 [ 70 - 15]
= 10 × 55
= 550
I hope this helps you.
: )
a + b + c = 10 ----( 1 )
ab + bc + ca = 15 ----( 2 )
2( ab + bc + can ) = 30 ---( 3 )
a² + b² + c² = ( a +b+c)²-2( ab+bc+ca)
= 10² - 30
= 70 --- ( 4 )
Now ,
( a +b+c)[a²+b²+c²-(ab+bc+ca)]
= 10 [ 70 - 15]
= 10 × 55
= 550
I hope this helps you.
: )
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