Answer: 11
Step-by-step explanation:
A/b times b/c is = ab/bc
which can be written as a/c times b/b
anything over itself is 1 so b/b is one
a/b times b/c = a/c
Cos α = sin (90-α) so cos 19 = sin 90-19 = sin 71
The original expression is equal to 0 because anything multiplied by 0 is equal to 0. Solve inside the brackets for the possible answer choices to find what will equal 0.
Start with the first expression. Add 4 and negative 4 will become 0, and -1 times 0 is equal to 0. Let's solve for the others just to be sure.
In the second expression, solving inside the brackets gives you 8. -1 times 8 is equal to -8.
Adding 4 and negative 4 in the third expression leaves you with 0. But, 1 + 0 is equal to 1.
Adding negative 4 and negative 4 gives you the answer of -8, and -1 times -8 is equal to 8.
Your answer is the first expression, or A.
