The period of a pendulum is given by the equation
t = 21
which of the following domains provide a real-
value period?
og 0
o g = 0
og> 0
o 920
done
where l is the length of the string suspending the
pendulum in meters, and g is the acceleration due
to gravity in m/s2

Step-by-step explanation:

Among the options, the most reasonable is g > 0, because the movement of a pendulum depends on gravity, it's the reason of the movement actually, because the gravity is the acceleration of such oscillation.

Moreover, without gravity there weren't any pendulum movement, remember that acceleration refers to the change of velocity, which is what happens in all oscillations of a pendulum. If you think about it, you will realize that a pendulum stops in extreme points, then goes back, this movement tend to be periodical, because the gravity is approximately constant basically.

Therefore the right answer is g > 0.

the formula of a slope:

from a table we have

substitute:

the slope of f(x) is -1.

the graph of funcfion g(x) is a horizontal line. the slope of a horizontal line is equal 0. therefore the slope of g(x) is 0.

-1 < 0