Answer:
71.6 degrees
Step-by-step explanation:
Given the vectors
u= <8,4> v = <9.-9> (5 points)
u*v = (8, 4)*(9, -9)
u*v = 8(9)+(4)(-9)
u*v = 72 - 36
u*v = 36
|u| = √8²+4²
|u| = √64+16
|u| = √80
|v| = √9²+9²
|v| = √81+81
|v| = √162
Using the formula
u*v = ||u||v| cos theta
36 = √80(√162)cos theta
36 = √12960 cos theta
cos theta = 36/√12960
cos theta = 36/113.8
cos theta = 0.3162
theta = arccos(0.3162)
theta = 71.56 degrees
Hence the angle between the given vectors to the nearest tenth of a
degree is 71.6 degrees
Answer:
See proof below
Step-by-step explanation:
show that
sinx/1+cosx=tanx/2
From LHS
sinx/1+cosx
According to half angle
sinx = 2sinx/2 cosx/2
cosx = cos²x/2 - sin²x/2
cosx = cos²x/2 - (1- cos²x/2)
cosx = 2cos²x/2 - 1
cos x + 1 = 2cos²x/2
Substitute into the expression;
sinx/1+cosx
= (2sinx/2 cosx/2)/2cos²x/2
= sinx.2/cos x/2
Since tan x = sinx/cosx
Hence sinx/2/cos x/2 = tan x/2 (RHS)
This shows that sinx/1+cosx=tanx/2
<span>f(x)=2x+5
then
</span><span>f(4)=2(4) +5 = 8 + 5 = 13
hope it helps</span>
22 is the answer for 23x-1 for x=1
