Option A

<em><u>Solution:</u></em>
Given that we have to rewrite with only sin x and cos x
Given is cos 3x

We know that,

Therefore,
---- eqn 1
We know that,


Substituting these values in eqn 1
-------- eqn 2
We know that,

Applying this in above eqn 2, we get



Therefore,

Option A is correct
Answer:
I will help u if u help me
Step-by-step explanation:
2. Find the area of the parallelogram.
A.38cm
B.60cm
C.70cm
D.186cm
Answer:
We have to use the formule to calculate the vertex which is: V(-b/2a;4ac-b^2/4a)
A) y=x+7 where a=1 b=0 and c=7
By replacing we have: V(0;28/4) V(0;7)
B) y=-x where a=-1 b and c=0 so V(0,0)
Answer:
t=+4.06
Step-by-step explanation:
when the baseball hits the ground, the height will be 0.
h=0we are given that h=−16t2+64t+4.
this means that the height is 0 when −16t2+64t+4=0.−16t2+64t+4=0divide both sides by 4:−4t2+16t+1=04=0−4t2+16t+1=0 can be solved using the quadratic formula:t=−b±√b2−4ac2a, where at2+bt+c=0.at2+bt+c=−4t2+16t+1a=−4,b=16,c=1t=−b+√b2−4ac2aor−b−√b2−4ac2a−b+√b2−4ac2a=−16+√272−8=−0.06..−b−√b2−4ac2a=−16−√272−8=4.06 (3s.f.)we have 2 values for t:−0.06 and 4.06.
since time cannot be negative, only the positive value can be taken.
this is 4.06, to 3 significant figures.the time taken is 4.06 seconds.
For this case we have the following equation:

Let 
We have:

By definition, given an equation of the form 
The quadratic formula, to find the solution can be written as:

In this case we have:

Substituting in the quadratic formula we have:
See attached image
Answer:
Option B