Which rational expression is undefined when a=1

is undefined at a = 1

Step-by-step explanation:

Required

Which is undefined at a = 1

An expression is undefined when its denonimator equals 0.

So, we have to test the denominator of each.

(A): 7a + 7

This gives:

(B): 5a - 10

This gives:

(C) -a² + 1

This gives

(D) 3a²

This gives:

Notice that only (C) equals 0.

Hence:

is undefined at a = 1

hope this !

step-by-step explanation:

d = distance between moon and sun, which in this problem is the hypotenuse of a right triangle.  

the distance y is the side opposite to angle x in the right triangle.   use the definition of the sine function from basic trigonometry.

sin(x) = y/d ⇒

d = y/sin(x)

how am i supposed to answer

step-by-step explanation: