a. diketahui tan B = 6/8, nilai sin B = ....? b. diketahui cos A = 4/5, nilai cot A = ....? bantu ya, terima kasih !!!

a.
tan B = 6/8 = y/x
⇒r² = 6² + 8²
⇒r² = 100
⇒r = 10
↓
sin B = y/r
sin B = 6/10 = 3/5

b.
cos A = 4/5 = x/r
⇒y² = 5² - 4²
⇒y² = 9
⇒y = 3
↓
cot A = x/y
cot A = 4/3

[tex]\displaystyle \tan b=\frac68\\\frac yx=\frac34\\\\y=3\\x=4\\r=\sqrt{x^2+y^2}\\=5\\\\\sin b=\frac{y}{r}\\\boxed{\boxed{\sin b=\frac35}}\\\\\cos a=\frac45\\\frac xr=\frac45\\\\x=4\\r=5\\y=\sqrt{r^2-x^2}\\y=3\\\\\cot a=\frac{x}{y}\\\boxed{\boxed{\cot a=\frac43}}[/tex]