Tommorow is my exam .plz give me answers of these questions.
1] if X+Y =8 and XY =15,find Xraise to power of 2 + Y raise to power of 2.
2] if X = 3 -2*root 2,then find value of X raise to power of 2 -1/X raise to power of 2.
1=
x+y=8
xy=15 find x2+y2
using the identity
(x+y)2 = x2 +y2+2xy
putting the values
82=x2+y2+2*15
64=x2+y2+30
x2+y2=64-30=34
ans=34
2=
x=3-2√2 find x2-1/x2
1/x=1/3-2√2
1/x=1/3-2√2 *3+2√2/3+2√2 Rationalising the denominator
3+2√2
putting the values
(3-2√2)2-(3+2√2)2
(9+8-2*3*2√2)-(9+8+2*3*2√2) (((( a2+b2+2ab and a2+b2-2ab)))))
(17-12√2)-(17+12√2)
17-12√2-17-12√2
-24√2
ans=-24√2
Hope this helps