HELP ME SIR my name is josephpls help me with these questions im having exams day after tomorrow
1. if x-y=4 and xy=21 , find x^3 - y^3
2. 64X^3/125 - 8 - 96X^2/25 + 48X/5
3. 2(A+B)^2 - 9(A+B) - 5
4.IF X+Y=12, XY=32. FIND X^2+Y^2
5.IF 4X^2+Y^2=40 AND XY=6 , FIND 2X+Y
SIR PLEASE SEND TOMORROW ITSELF .
THANK YOU
Dear Student,
Please find below the solution to the asked query:
1 ) Given : x - y = 4 and x y = 21
We know : a3 - b3 = ( a - b )3 + 3 a b ( a - b ) , So
x3 - y3 = ( x - y )3 + 3 x y ( x - y ) , Substitute given values we get :
x3 - y3 = 43 + 3 ( 21 ) ( 4 ) = 64 + 252 = 316 ( Ans )
3 ) We have : 2 ( A + B )2 - 9 ( A + B ) - 5 , Now we use splitting the middle term method and get :
2 ( A + B )2 - 10 ( A + B ) + ( A + B ) - 5
2 ( A + B )[ ( A + B ) - 5 ] + 1 [ ( A + B ) - 5 ]
[ 2 ( A + B ) + 1 ][ ( A + B ) - 5 ]
[ 2 A + 2 B + 1 ][ A + B - 5 ] ( Ans )
Hope this information will clear your doubts about topic.
For remaining queries we request you to post them in separate threads to have rapid assistance from our experts.
Regards
Please find below the solution to the asked query:
1 ) Given : x - y = 4 and x y = 21
We know : a3 - b3 = ( a - b )3 + 3 a b ( a - b ) , So
x3 - y3 = ( x - y )3 + 3 x y ( x - y ) , Substitute given values we get :
x3 - y3 = 43 + 3 ( 21 ) ( 4 ) = 64 + 252 = 316 ( Ans )
3 ) We have : 2 ( A + B )2 - 9 ( A + B ) - 5 , Now we use splitting the middle term method and get :
2 ( A + B )2 - 10 ( A + B ) + ( A + B ) - 5
2 ( A + B )[ ( A + B ) - 5 ] + 1 [ ( A + B ) - 5 ]
[ 2 ( A + B ) + 1 ][ ( A + B ) - 5 ]
[ 2 A + 2 B + 1 ][ A + B - 5 ] ( Ans )
Hope this information will clear your doubts about topic.
For remaining queries we request you to post them in separate threads to have rapid assistance from our experts.
Regards