Question 16 (Essay Worth 7 points)

Verify the identity.

tan (x + π/2) = -cot x

Step-by-step explanation:

We know that tan=sin/cos, so tan(x+π/2)=

Then, we know that sin(u+v)=sin(u)cos(v)+cos(u)sin(v),

so our equation is then

Then, cos(u+v)=cos(u)cos(v)-sin(u)sin(v), so our expression is then

75 tickets have been sold so far.

step-by-step explanation:

in this question it is clearly mentioned that 45 children's tickets have been sold and this number is 60% of the total tickets sold.

now let's assume the total number of tickets sold be x.

then 60% of x = 45

⇒

⇒ x(.6) = 45

by dividing with .6 on both the sides of the equation

⇒ x = 75

therefore 75 tickets have been sold so far.

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