Вправи: 556

556. Спрости вираз.

a) (2x² – 1)(2x² + 1)(4x⁴ + 1) – (4x⁴ + 1)² = (4x⁴ – 1)(4x⁴ + 1) – (16x⁸ + 8x⁴ + 1) = 16x⁸ – 1 – 16x⁸ – 8x⁴ – 1 = –8x⁴ – 2;

б) 4(4a⁴ – c⁸) – (2a – c²)(2a + c²)(4a² + c⁴) = 16a⁴ – 4c⁸ – (4a² – c⁴) • (4a² + c⁴) = 16a⁴ – 4c⁸ – (16a⁴ – c⁸) = 16a⁴ – 4c⁸ = –3c⁸.