1)х^4-16х^2=(x^2)^2-(4)^2=(x^2-4x)(x^2+4x)
2) -4х^2-8ху-4у^2=-4(x^2+2xy+y^2)=-4(x+y)^2
x² - 1 > 0
(x - 1)(x + 1) > 0
+ - +
________₀________₀________
- 1 1
//////////////// ///////////////////
x ∈ ( - ∞ ; - 1) ∪ (1 ; + ∞)
A) 50-x=7² ==>x=1
b) 60+5x=5²²==>5x=25-60 ==>5x=-35 ==>x= - 7
c) 44 + x =6² ==>x=36-44 = 1
3*10^-1=0.3
5*10^-3=0.005
4-10^-4=0.0004
0.3+0.005+0.0004=0.3054