Recall that to get the x-intercepts, we set the f(x) = y = 0, thus
![\bf \stackrel{f(x)}{0}=-4cos\left(x-\frac{\pi }{2} \right)\implies 0=cos\left(x-\frac{\pi }{2} \right) \\\\\\ cos^{-1}(0)=cos^{-1}\left[ cos\left(x-\frac{\pi }{2} \right) \right]\implies cos^{-1}(0)=x-\cfrac{\pi }{2} \\\\\\ x-\cfrac{\pi }{2}= \begin{cases} \frac{\pi }{2}\\\\ \frac{3\pi }{2} \end{cases}](https://tex.z-dn.net/?f=%5Cbf%20%5Cstackrel%7Bf%28x%29%7D%7B0%7D%3D-4cos%5Cleft%28x-%5Cfrac%7B%5Cpi%20%7D%7B2%7D%20%20%5Cright%29%5Cimplies%200%3Dcos%5Cleft%28x-%5Cfrac%7B%5Cpi%20%7D%7B2%7D%20%20%5Cright%29%0A%5C%5C%5C%5C%5C%5C%0Acos%5E%7B-1%7D%280%29%3Dcos%5E%7B-1%7D%5Cleft%5B%20cos%5Cleft%28x-%5Cfrac%7B%5Cpi%20%7D%7B2%7D%20%20%5Cright%29%20%5Cright%5D%5Cimplies%20cos%5E%7B-1%7D%280%29%3Dx-%5Ccfrac%7B%5Cpi%20%7D%7B2%7D%0A%5C%5C%5C%5C%5C%5C%0Ax-%5Ccfrac%7B%5Cpi%20%7D%7B2%7D%3D%0A%5Cbegin%7Bcases%7D%0A%5Cfrac%7B%5Cpi%20%7D%7B2%7D%5C%5C%5C%5C%0A%5Cfrac%7B3%5Cpi%20%7D%7B2%7D%0A%5Cend%7Bcases%7D)
Answer:
The value of k is 5/8
Step-by-step explanation:
The value of k is found by dividing the numerator of the original ratio, 5, by the sum of the numerator and denominator of the ratio
When finding a point, P, to partition a line segment AB into the ratio a/b, we find a ratio c = a / (a + b)
According to this formula we find the value of k.
k = a/(a+b)
where a = 5
b = 3
Now plug the values in the formula:
k = 5/(5+3)
k = 5/8 ....
do it yourself
Step-by-step explanation:
Answer:
x = 5/(10 - a - b)
Step-by-step explanation:
Solve for x:
4 + 3 x - a x = 9 - 7 x + b x
Collect in terms of x:
x (3 - a) + 4 = 9 - 7 x + b x
Collect in terms of x:
x (3 - a) + 4 = x (b - 7) + 9
Subtract (b - 7) x + 4 from both sides:
x (10 - a - b) = 5
Divide both sides by 10 - a - b:
Answer: x = 5/(10 - a - b)