Помогите решить задания по алгебре:

№1

1) (5 - 2 * 1/2) ² - (5 + 2 * 1/2) ² =

2) (27 - 2 * 1/27) ² - (27 + 2 * 1/27) ² =

3) (a - 2b) ² * (a + 2b) ², если ab = 1/8

1) (5-2,5-5-2,5) (5-2,5+5+2,5) = - 5 (10) = - 50

2) (27-2 1/27-27-2 1/27) (27-2 1/27+27+2 1/27) = - 4 2/27*2*27=-110/27 * (2*27) = - 220

3) ((a-2b) (a+2b)) ^2 = (a^2-4b^2) ^2=a^4+16b^4-8a^2b^2=a^4+16b^4-1/8