Answer: ab =6
have:
=> a + b + 1 = ab
⇔ a + b + 1 - ab = 0
⇔ b - 1 - a(b - 1) + 2 = 0
⇔ (b - 1)(1 - a) = -2
because a and b are postive integers => (b - 1) and (1 - a) also are integers
=> (b - 1) ∈ {-1; 1; 2; -2;}
(1 -a) ∈ {-1; 1; 2; -2;}
because (b -1).(1-a) = -2 => we have the table:
b - 1 -1 1 2 -2
1 - a 2 -2 -1 1
a -1 3 2 0
b 0 2 3 -1
a.b 0 6 6 0
because a and b are postive integers
=> (a;b) = (3;2) or (a;b) = (2;3)
=> ab = 6
Step-by-step explanation:
Suppose that a>b>1, then
and
Therefore, since 2<3<7,
Choose an arbitrary x>1. You have that a takes the greatest values at x, c takes the smallest value at x. Thus,
a>b>c and
Answer: correct option is B.
Answer:
Step-by-step explanation:
The total surface area of this triangular prism consists of three rectangles and two triangles. Adding the areas of each of these shapes allows us to find the total surface area of this 3D figure:
Area of both triangles:
Area of all three rectangles:
Therefore, the total surface area of this figure is:
