Answer: 2sin^2x+sin2x+cos2x=0 ..... (1).
By using the trigonometric identities below :
sin2x=2sinxcosx
cos2x=cos^2x-sin^2x
We substitute the trigonometric identities into (1).
2sin^2x+2sinxcosx+cos^2x-sin^2x=0
By combining like terms .
sin^2x+2sinxcosx+cos^2x=0.....(2)
The equation (2) is equivalent to the following expression (3).
(sinx+cosx)(sinx+cosx)=0 .....(3).
sinx+cosx=0
cosx=-sinx
divide both sides by cosx
1=-sinx/cosx
-1=sinx/cosx
sinx/cosx=tanx
substitute
-1=tanx
tanx=-1
tangent is negative in 2nd and 4th quadrants
tan135º=-1 (one answer)
tan315º=-1 (second answer)
Step-by-step explanation:
Please refer to the trigonometric identities used and explained above .
Answer:
x-- 3
Step-by-step explanation:
9 a
------ = -----
a 5
a^2 = 45
a = 3<span>√5
</span>
4 b
------ = -----
b 5
b^2 = 20
b = 2√5
answer:
a = 3√5
b = 2√5
hope it helps
The price of 1 liter motor oil is $0.97
Given:
μ = $3.26 million, averaged salary
σ = $1.2 million, standard deviation
n = 100, sample size.
Let x = random test value
We want to determine P(x>4).
Calculate z-score.
z = (x - μ)/ (σ/√n) = (4 - 3.26)/(1.2/10) = 6.1667
From standard tables,
P(z<6.1667) = 1
The area under the distribution curve = 1.
Therefore
P(z>6.1667) = 1 - P(z<=6.1667) = 1 - 1 = 0
Answer: The probability is 0.
