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Squaring Out Brackets. Double Bracket Reminder. Multiply out the brackets below :. ( 2x + 4 ) ( 3x – 8 ). = 2x. ( 3x - 8 ). +4. ( 3x - 8 ). = 6x 2. -16x. +12x. -32. = 6x 2. -4x. -32. Multiplying Out (x + y ) 2. Consider how to multiply out the brackets below:. (x + y ) 2.
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Double Bracket Reminder. Multiply out the brackets below : ( 2x + 4 ) ( 3x – 8 ) = 2x ( 3x - 8 ) +4 ( 3x - 8 ) = 6x2 -16x +12x -32 = 6x2 -4x -32
Multiplying Out (x + y ) 2 Consider how to multiply out the brackets below: (x + y ) 2 If 6 = 6 x 6 and 7 = 7 x 7 then ….. = ( x + y )( x + y ) = x ( x + y ) + y ( x + y ) = x 2 + xy + xy + y 2 Key Result: (x + y ) 2 = x 2 + 2xy + y 2 = x 2 + 2xy + y 2
How To Multiply Out ASquare Bracket. (x + y ) 2 = x 2 + 2xy + y 2 The key result above gives us a shortcut method to square out any bracket. It tells us to do the following: (1) Square the first term of our expression. x2 (2) Take the product of the two terms and double them. 2xy (3) Square the second term . y2 By repeating these moves on any square bracket we can multiply out the bracket in one line.
Squaring Out Brackets. Square out the bracket below : (1) Square out the first term. (1) (2x + 3y)2 (2) Double the product of the terms. = 4x 2 +12xy +9y2 (3) Square out the last term. (2) (5x + 2y)2 (1) Square out the first term. = 25x 2 +20xy +4y2 (2) Double the product of the terms. (3) Square out the last term.
What Goes In The Box ? Multiply out the brackets below: (1) ( 4x + 3y)2 = 16x 2 +24xy + 9y 2 (2) ( 2w + 5m) 2 = 4w 2 +20wm + 25m2 (3) ( 6f + 3g) 2 = 36f 2 +36fg + 9g 2 (4) ( 7b + 6a) 2 = 49b 2 +84ab + 36a 2 (5) ( 9y + 9w) 2 = 81y 2 +162yw + 81w2
Squaring Out Brackets With Negatives Multiply out the bracket below which contain a negative sign : ( 4w – 6t ) 2 ( 4w x 4w) ( 4w x – 6t ) (– 6t x – 6t) = + + 16 w 2 - 24wt + 36 t 2 =
What Goes In The Box ? 2 Multiply out the brackets below : (1) ( 4 w – 6 f )2 = 16w 2 - 48wf +36f 2 (2) ( 7 r – 3 g )2 = 49r 2 - 42rg +9g 2 25t 2 - 20ht +4h 2 (3) ( 5 t – 2 h )2 = 81d 2 - 54ad +9a 2 (4) ( 9 d – 3 a )2 =