which option is correct que no. 22
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I think 22 should be it's right answer
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Given that x+y+z=5
xy+yz+zx=7
x3+y3+z3-3xyz
now we know that x3+y3+z3-3xyz=(x+y+z)×(x2+y2+z2-xy-yz-zx)..(1)
again(x+y+z)^2=x2+y2+z2+2xy+2yz+2zx
replace the value
5^2=x^2+y^2+z^2+2(xy+yz+zx)
replace the value of xy+yz+zx=7
x2+y2+z2+2(7)=25
x2+y2+z2+14=25
x2+y2+z2=25-14
x2+y2+z2=11.....(2)
replacing this value in the of equation(1)
x3+y3+z3-3xyz=(x+y+z)×(x2+y2+z2-(xy+yz +zx)
x3+y3+z3-3xyz=5×(11-7)
x3+y3+z3-3xyz=5×4
x3+y3+z3-3xyz=20
so, option (a) is correct sweet frns
if u satisfied please follow me
xy+yz+zx=7
x3+y3+z3-3xyz
now we know that x3+y3+z3-3xyz=(x+y+z)×(x2+y2+z2-xy-yz-zx)..(1)
again(x+y+z)^2=x2+y2+z2+2xy+2yz+2zx
replace the value
5^2=x^2+y^2+z^2+2(xy+yz+zx)
replace the value of xy+yz+zx=7
x2+y2+z2+2(7)=25
x2+y2+z2+14=25
x2+y2+z2=25-14
x2+y2+z2=11.....(2)
replacing this value in the of equation(1)
x3+y3+z3-3xyz=(x+y+z)×(x2+y2+z2-(xy+yz +zx)
x3+y3+z3-3xyz=5×(11-7)
x3+y3+z3-3xyz=5×4
x3+y3+z3-3xyz=20
so, option (a) is correct sweet frns
if u satisfied please follow me
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