Interval#!#Sign Of Expression

If x<5, then the sign of the expression 2x+7-5x^(2) is

Find the sign of the expression sin theta+cos theta when theta=100^(@)

For 2

If theta = 5pi/9 the sign of the expression cos theta + sin theta is____.

Define Poisson's ratio.Write an expression for it. What is the significance of negative sign in this expression ?

Define Poisson's ratio. Write an expression for it. What is the significance of negative sign in this expression ?

The interval (2,4) can be expressed in rule method as