Step-by-step explanation:
the answer is D and is that all ur work?
Answer:
<em>cos a = -1.28 and 0.78</em>
Step-by-step explanation:
The question is not properly written. This is the correct question:
If sina×tan(a) = 1/2, find cosa
According to trigonometry identity;
tan a = sina/cosa
sina×tan(a) = sin a * sina/cosa
sin²a/cos a = 1/2
(1-cos²a)/cosa = 1/2
Cross multiply
2(1-cos²a) = cos a
2 - 2 cos²a = cos a
2cos²a + cos a - 2 = 0
Let P = cos a
2P² + P -2 = 0
P = -1 ±√1-4(2(2)/2(2)
P = -1 ±√1+16/4
P = -1 ±√17/4
P = -1±4.12/4
P = -1-4.12/4 and -1+4.12/4
P = -5.12/4 and 3.12/4
P = -1.28 and 0.78
Since P = cos a
<em>Hence cos a = -1.28 and 0.78</em>
It would go like this 6(b-4)>30 would then be 6b-24>30 then you would have to add 24 to both the -24 and the 30 to get 6b>54 the you would have to divide 54 by 6 and after that your answer would be b> 9
Answer:
64,98*63.98
Step-by-step explanation: