A2
a)...=(2a-5b)(2a+5b)
b)...=(3x-y)^2
в)...=2a(c^2-16a^2)=2a(c-4a)(c+4a<span>)
A3
a)...=(0.2a-0.5b^2)
b)...=(3x+1)^2-4y^2=(</span>(3x+1)-2y)((3x+1)+2y)
<span>в)...=(2c-3)(4C^2+6c+9)
</span>
А^2 - b^2 + 3( a - b )^2 = ( a - b )( a + b ) + 3( a - b )^2 = ( a - b )( a + b + 3a - 3b ) = ( a - b )( 4a - 2b )
на фото..................
1)4x/3+π/6=7π/6+2n,n∈z
4x/3=π+2πn,n∈z
x=3π/4+3πn/2,n∈z
-2π≤3π/4+3πn/2<2π
-8≤3+6n<8
-11≤6n<5
-11/6≤n<5/6
n=-1⇒x=3π/4-3π/2=-3π/4
n=0⇒x=3π/4
2)4x/3+π/6=11π/6+2πk,k∈z
4x/3=5π/3+2πk,k∈z
x=5π/4+3πk/2;k∈z
-2π≤5π/4+3πk/2<2π
-8≤5+6k<8
-13≤6k<3
-13/6≤k<1/2
k=-2⇒x=5π/4-3π=-7π/4
k=-1⇒x=5π/4-3π/2=-π/4
k=0⇒x=5π/4