Answer: b. 0.8413
Step-by-step explanation:
Given : The average time taken to complete an exam, X, follows a normal probability distribution with 
and 
.
Then, the probability that a randomly chosen student will take more than 30 minutes to complete the exam will be :-
![P(x>30)=P(z>\dfrac{30-60}{30})\ \ [\because\ z=\dfrac{x-\mu}{\sigma} ]\\\\=P(z>-1)=P(z-z)=P(Z](https://tex.z-dn.net/?f=P%28x%3E30%29%3DP%28z%3E%5Cdfrac%7B30-60%7D%7B30%7D%29%5C%20%5C%20%5B%5Cbecause%5C%20z%3D%5Cdfrac%7Bx-%5Cmu%7D%7B%5Csigma%7D%20%5D%5C%5C%5C%5C%3DP%28z%3E-1%29%3DP%28z%3C1%29%5C%20%5C%20%5C%20%5B%5Cbecause%5C%20P%28Z%3E-z%29%3DP%28Z%3Cz%29%5D%5C%5C%5C%5C%3D%200.8413)
[using z-value table]
Hence, the probability that a randomly chosen student will take more than 30 minutes to complete the exam = 0.8413
We are given a graph of a quadratic function y = f(x) .
We need to find the solution set of the given graph of a quadratic function .
<em>Note: Solution of a function the values of x-coordinates, where graph cut the x-axis.</em>
For the shown graph, we can see that parabola in the graph doesn't cut the x-axis at any point.
It cuts only y-axis.
Because solution of a graph is only the values of x-coordinates, where graph cut the x-axis. Therefore, there would not by any solution of the quadratic function y = f(x).
<h3>So, the correct option is 2nd option :∅.</h3>
We know that sin(a-b) = sina.cosb - cosa.sinb
if a=70 & b=10 the sin(70-10) = sin(60) = √3/2
Sin70cos10-cos70sin10 = sin60 = √3/2
