Answers

2014-05-03T15:42:29+05:30
2. ans:
3*7-2√42-3√42+2*6
=21-5√42=12
=33-5√42
0
2014-05-04T11:16:57+05:30
x/a+y/b=2 =>xb+ya=2ab=>abx+a^2y=2a^2b
ax-by=a^2-b^2=>abx-b^2y=a^2b-b^3
solving the 2 equations, we get
y(a^2+b^2)=2a^2b-a^2b+b^3=a^2b+b^3=b(a^2+b^2) \\ =>y=b, x=a.

 (\sqrt{7}-\sqrt{6})(3\sqrt{7}-2\sqrt{6})=(3*7+2*6-3\sqrt{42}-2\sqrt{42})=33-5\sqrt{42}
0