(a + b) ² = a ² + b ² is wrong because 2ab is not there to make the equation complete(a + b) ² = a ² + 2ab + b ²The square on the top left hand corner is axa=a ²The 2 small rectangle is equal to 2(ab)=2abThe big rectangle is equal tobxb= b ²If you join up a ² ,2ab and b ²it will form a ² + 2ab + b ²which is directly equal to (a + b) ²
No it is not a² + b²take the top left portion as A the top right portion as B the bottom left portion as C and the bottom right portion as DA=a²B=abC=abD=b²the whole area=a²+ab+ab+b²=a² + 2ab + b²
(a+b)²=(a+b)(a+b) =a²+ab+ba+b² =a²+2ab+b²
Splendid! As clearly illustrated in the diagram, the 4 areas give a total area of a²+2ab+b². So next time u forgot the expansion, u can draw up a similar diagram to help u derive the answer.
whew.......hate those boxes..its kinda troublesome,so i'll justremember the formula..(a+b)(a+b)=(axa)+2(a)(b)+(bxb)i could remember these well..so ... Good Luck guys =D
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(a + b) ² = a ² + b ² is wrong because 2ab is not there to make the equation complete
(a + b) ² = a ² + 2ab + b ²
The square on the top left hand corner is axa=a ²
The 2 small rectangle is equal to
2(ab)=2ab
The big rectangle is equal to
bxb= b ²
If you join up a ² ,2ab and b ²
it will form a ² + 2ab + b ²
which is directly equal to
(a + b) ²
No it is not a² + b²
take the top left portion as A the top right portion as B the bottom left portion as C and the bottom right portion as D
A=a²
B=ab
C=ab
D=b²
the whole area=a²+ab+ab+b²=a² + 2ab + b²
(a+b)²=(a+b)(a+b)
=a²+ab+ba+b²
=a²+2ab+b²
Splendid! As clearly illustrated in the diagram, the 4 areas give a total area of a²+2ab+b².
So next time u forgot the expansion, u can draw up a similar diagram to help u derive the answer.
whew.......hate those boxes..
its kinda troublesome,so i'll just
remember the formula..
(a+b)(a+b)=(axa)+2(a)(b)+(bxb)
i could remember these well..
so ... Good Luck guys =D
Post a Comment