Find all solutions to the equation. 7 sin2x - 14 sin x 2 = -5

The all solution of given trigonometrical equation is + 2πn   .

Step-by-step explanation:

Given trigonometrical equation as :

7 - 14 sin x + 2 = - 5

Now, Rearranging the equation

7 - 14 sin x + 2 + 5 = 0

Or, 7 - 14 sin x + 7 = 0.

Taking 7 as common

So,   - 2 sin x + 1 = 0.

∵The standard form of quadratic equation

a x² + b x + c = 0

So, breaking the mid term we get

- sin x - sin x + 1 = 0.

Or, sin x (sin x - 1) - 1 (sin x - 1) = 0

Or, (sin x - 1) (sin x - 1) = 0

Or, (sin x -1) = 0 and (sin x - 1) = 0

So, sin x = 1

∴ x =

i.e x = 90°

Or, ∠x =

And for all solution + 2πn  , where n∈ 0  to ....

Hence, The all solution of given trigonometrical equation is + 2πn   . Answer

345

step-by-step explanation:

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional