C=15+3. Combine like terms. C=18.
Answer:
See Explanation
Step-by-step explanation:
<em>Question like this are better answered if there are list of options; However, I'll simplify as far as the expression can be simplified</em>
Given

Required
Simplify

Represent
with a
Represent
with b
The expression becomes

Factorize



Recall that

The expression
becomes

..............................................................................................................................
In trigonometry

Subtract
from both sides


..............................................................................................................................
Substitute 1 for
in 

Open Bracket
------------------This is an equivalence

Solving further;
................................................................................................................................
In trigonometry


Substitute the expressions for secx and tanx
................................................................................................................................
becomes

Open bracket


Add Fraction
------------------------ This is another equivalence
................................................................................................................................
In trigonometry

Make
the subject of formula

................................................................................................................................
Substitute the expressions for
for 

Open bracket

---------------------- This is another equivalence
Answer:
(c) H0 should be rejected
Step-by-step explanation:
Null hypothesis (H0): population mean is equal to 5
Alternate hypothesis (Ha): population mean is greater than 5
Z = (sample mean - population mean) ÷ (sd/√n)
sample mean = 5.3, population mean = 5, sd = 1, n = 500
Z = (5.3 - 5) ÷ (1/√500) = 0.3 ÷ 0.045 = 6.67
Using the normal distribution table, for a one tailed test at 0.01 significance level, the critical value is 2.326
Conclusion:
Since 6.67 is greater than 2.326, reject the null hypothesis (H0)
Answer:
This sentence is true.
Step-by-step explanation: