Answer:
roots : 4, -4, i, -i
Step-by-step explanation:
This gets a bit tricky.
We have to substitude x^2 as u in this problem.
Now to rewrite x^4 − 15x^2 − 16 = 0 with u, we get
u^2 - 15u - 16 = 0
( u - 16) (u + 1)
U = 16
U = -1
<em>This is not the end of the problem. </em>
Now we have to substitute x^2 back to u.
x^2 = 16 --> we get the roots 4 and -4
x^2 = -1 --> we get the roots i and -i
tadah!
#5,
it says that the angle on top is 221, so you subtract that from 360,
360-221= the rest..... 139
Now in that 139, you can see that there is a triangle with a right angle. so you can subtract 90 degrees from 139
139-90= 49
49 is the number you use to solve the rest.
3x + 4x = 7x
so 7x = 49
and then you divide 7 from both sides to isolate x, and you get your answer
How to Divide Exponents With Different Bases:
Different Bases and Same Exponent. In this case, you can group the two bases into a quotient and apply the exponent. ...
Different Bases and Different Exponents. The expression b^4 / a^2 is equivalent to (b * b * b * b) / (a * a). ...
Order of Operations
