Răspuns:
Explicație pas cu pas:
1) ( 3x - 1)² = (3x)² - 2 × 3 x× 1 + 1² = 9 x² - 6 x + 1
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2) ( 5 - 2 x ) ( 5 + 2 x ) + ( 1 - 4 x )² = 25 - 4 x² + 1 - 8 x + 16 x² =
= 14 x² - 8 x + 26
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( 5 x - 2 x ) ( 5 + 2 x ) + ( 1 - 4x)² =
= 3 x ( 5 + 2 x ) + 1 - 8 x + 16 x² =
= 15 x + 6 x² + 1 - 8 x + 16 x² =
= 22 x² + 7 x + 1