化简 (a+3)(a+1)-4(a+1)

解答

化简

(a + 3) (a + 1) - 4 (a + 1)

a^{2} - 1

求解步骤

(a + 3) (a + 1) - 4 (a + 1)

展开

(a + 3) (a + 1) : a^{2} + 4 a + 3

= a^{2} + 4 a + 3 - 4 (a + 1)

展开

- 4 (a + 1) : - 4 a - 4

= a^{2} + 4 a + 3 - 4 a - 4

对同类项分组

= a^{2} + 4 a - 4 a + 3 - 4

s im pl i f y 3. 3^{2}

f a c t or 3 x - x^{3}

e x p an d (x + 1) (x - 2) (x - 4)

s im pl i f y (- 3 sin (t))^{2}

s im pl i f y \frac{56 \cdot 15}{35 \cdot 42}