Question

If -y sin 90 cos 30+sin 30 cos 90=4/5,then find y.

Answer 1

-ysin90cos30+sin30cos90=4/5
-y×1×root 3/2+1/2×0=4/5
-y×root 3/2=4/5
y= -4/5×2/root 3
y= -8/5 root 3

Answer 2

Answer:

$y=\frac{-8}{5\sqrt{3} }$

Step-by-step explanation:

The given Trigonometric expression is,

-y Sin90° Cos30°+Sin30° Cos90° = 4/5

We know that,

Sin90° = 1

Cos30° = $\frac{\sqrt{3} }{2}$

Sin30° = $\frac{1}{2}$

Cos90° = 0

Put this values in the given Trigonometric expression

$-y\times1 \times\frac{\sqrt{3} }{2} + \frac{1}{2} \times 0=\frac{4}{5} \\\frac{-\sqrt{3} }{2} y+0=\frac{4}{5} \\y=\frac{4}{5} \times\frac{-2}{\sqrt{3} } \\\therefore y=\frac{-8}{5\sqrt{3} }$

For more such questions, click on the below link.

https://brainly.in/question/2685053

#SPJ2