If x2+y2=47 and xy=192 then what is the value of 3(x+y)2+(x−y)2?
170
270
226
86
x2+y2=47……(1) xy=192……(2) (x+y)2=x2+y2+2xy =47+2×192=47+19=66 (x+y)2=66 Also, (x−y)2=x2+y2−2xy =47−19=28 ∴3(x+y)2+(x−y)2=3×66+28=226
If x2+y2=14 and xy=3, then find the value of 2(x+y)2−5(x−y)2.
If x2+y2=14 and xy=3, find the value of 2(x+y)2−5(x−y)2.