Answer:
Step-by-step explanation:
observe
||a–b+c|| = ||a+b+c||
(a-b+c)² = (a+b+c)²
(a+b+c)² – (a-b+c)² = 0
((a+b+c)+(a-b+c))((a+b+c)–(a-b+c)) = 0
(2a+2c)(2b) = 0
(a+c)b = 0
a•b + c•b = 0
||a||×||b||×cos(π/8) + ||c||×||b||×cos(θ) = 0
Answer:
x = 5, -3
Step-by-step explanation:
x² - 15 = 2x
x² - 2x - 15 = 0
(x - 5)(x + 3) = 0
Answer:
0<x<1
Step-by-step explanation:
(x+3)(x−4)<−12
FOIL
x^2 -4x+3x -12 <-12
x^2 -x -12 <-12
Add 12 to each side
x^2 -x -12+12 <-12+12
x^2 -x <0
Factor out an x
x(x-1) <0
Using the zero product property
x(x-1) =0
x=0 x-1=0
x=0 x=1
Check the ranges
x<0
x(x-1) <0
- * - >0
False
0<x<1
x(x-1) <0
+ * - <0
True
x>1
x(x-1) <0
+ * + >0
False
Answer:
x<-10
Step-by-step explanation:
10-2.5x>35
2.5x>10-35
2.5x>-25
x>-25/2.5
x>-10
x<-10
