Упростите выражение: (3x-1)(3x+1)+(3x+1)^2

Question

Упростите выражение:
(3x-1)(3x+1)+(3x+1)^2

Answer 1

(3х-1)(3х+1) + (3х+1)²=(3х+1)(3х-1+3х+1)=(3х+1)(6х)=18х²+6х

Comments

А разве не так? (3x-1) (3x+1) + (3x+1)^2 = 3x^2-1+3x^2+2*3x*1+1=6x^2+6x

Answer 2

( 3x - 1 )( 3x + 1 ) + ( 3x + 1 )² = 9x² - 1 + 9x² + 6x + 1 = 18x² + 6x 

Comments

А разве не так? (3x-1) (3x+1) + (3x+1)^2 = 3x^2-1+3x^2+2*3x*1+1=6x^2+6x

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( 3x - 1 )( 3x + 1 ) = ( 3x)^2 - 1^2 = 9x^2 - 1

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( a - b )( a + b ) = a^2 - b^2

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( 3x + 1 )^2 = ( 3x )^2 + 2 * 3x * 1 + 1 ^2 = 9x^2 + 6x + 1

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( a + b )^2 = a^2 + 2ab + b^2