Answer:
C
Step-by-step explanation:
hope this helps.
Answer:
x^2-2x-4=0
Δ=2^2-4*1*(-4)
Δ=4+16=20
VΔ=2V5
x1= (2+2V5)/2=1+V5
the answer is D
Step-by-step explanation:
Answer:
Add the exponents
Step-by-step explanation:
Product Rule: am ∙ an = am + n, this says that to multiply two exponents with the same base, you keep the base and add the powers.
EX:
x multiplied by x^5=x^6
Answer:
D
Step-by-step explanation:
X is 21
z is the same as 111
y is 48
Answer:
see explanation
Step-by-step explanation:
(4)
consider the left side
factor the numerator
cosx - cos³x = cosx(1 - cos²x)
![\frac{cosx(1-cos^2x)}{sinx}[/tex = [tex]\frac{cosxsin^2x}{sinx}](https://tex.z-dn.net/?f=%5Cfrac%7Bcosx%281-cos%5E2x%29%7D%7Bsinx%7D%5B%2Ftex%20%3D%20%5Btex%5D%5Cfrac%7Bcosxsin%5E2x%7D%7Bsinx%7D)
cancel sinx on numerator/denominator
= cosxsinx =right side ⇒ verified
(5)
Consider the left side
expand the factors
(1 + cotΘ)² + (1 - cotΘ)²
= 1 + 2cotΘ + cot²Θ + 1 - 2cotΘ + cot²Θ
= 2 + 2cot²Θ
= 2(1 + cot²Θ) ← 1 + cot²Θ = cosec²Θ
= 2cosec²Θ = right side ⇒ verified
(6)
Consider the left side
the denominator simplifies to
cosxtanx = cosx ×
= sinx

= sinx(
+
)
=
+ 
= tanx + 1 = right side ⇒ verified