EX. 3 SI 4 VA ROG MULT !!!! OFER COROANA SI 50 PUNCTE
Răspunsuri la întrebare
Răspuns:
Explicație pas cu pas:
3. Se foloseste a^2 - b^2 = (a - b)(a + b)
36b^4 - 25 = (6b^2 - 5)(6b^2 + 5)
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25a^4 - 1 = (5a^2 - 1)(5a^2 + 1)
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0,04x^2 - 9y^2/16 = (0,4x - 3y/4)(0,4x + 3y/4)
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(6x + 2)^2 - 100y^8 = (6x + 2 -10y^4)(6x + 2 + 10y^4)
________________
4.
4a^2 - 4a + 1 - 5a(2a - 1) = (2a - 1)^2 - 5a(2a - 1) = (2a - 1)(2a - 1 - 5a) =
(2a - 1)(-3a - 1) = (1 - 2a)(3a + 1)
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9a^2 + 6a + 1 - 2a(3a + 1) = (3a + 1)^2 - 2a(3a + 1) = (3a + 1)(3a + 1 - 2a)
= (3a + 1)(a + 1)
Răspuns:
Explicație pas cu pas:
Ex3 a) 36b⁴-25=(6b²)²-5²=(6b²-5)(6b²+5).
b) 0,04x²-(9/16)·y²=(0,2x)²-((3/4)y)²=(0,2x-(3/4)y)(0,2x+(3/4)y).
c) 25a⁴-1=(5a²)²-1²=(5a²-1)(5a²+1).
d) (6x+2)²-100y⁸=(6x+2)²-(10y⁴)²=(6x+2-10y⁴)(6x+2+10y⁴).
ex4 a) 4a²-4a+1-5a(2a-1)=(2a)²-2·2a·1+1²-5a(2a-1)=(2a-1)²-5a(2a-1)=(2a-1)·(2a-1-5a)=(2a-1)(-3a-1)=-(2a-1)(3a+1)=(1-2a)(1+3a).
b) 9a²+6a+1-2a(3a+1)=(3a)²+2·3a·1+1²-2a(3a+1)=(3a+1)²-2a(3a+1)=(3a+1)(3a+1-2a)=(3a+1)(a+1).