$@Mốc$
+) Ta có:
$cot ∝$.$tan ∝$ = $1$
⇔ `\frac{3}{5}`.$tan ∝$ = $1$
⇔ $tan ∝$ = `\frac{5}{3}`
+) Ta có:
`\frac{1}{cos^{2}∝}` = `1+tan^{2}∝`
⇔`\frac{1}{cos^{2}∝}` = `1+\frac{25}{9}`
⇔`\frac{1}{cos^{2}∝}` = `\frac{34}{9}`
⇔ `cos^{2}∝` = `\frac{9}{34}`
⇔ `cos∝` = $\sqrt[]{\frac{9}{34}}$
⇔ `cos∝` = $\frac{\sqrt[]{9}}{\sqrt[]{34}}$
⇔`cos∝` = $\frac{3}{\sqrt[]{34}}$
⇔`cos∝` = $\frac{3\sqrt[]{34}}{34}$
+) Ta có:
`\frac{1}{sin^{2}∝}` = `1+cot^{2}∝`
⇔`\frac{1}{sin^{2}∝}` = `1+\frac{9}{25}`
⇔`\frac{1}{sin^{2}∝}` = `\frac{34}{25}`
⇔ `sin^{2}∝` = `\frac{25}{34}`
⇔ `sin∝` = $\sqrt[]{\frac{25}{34}}$
⇔ `sin∝` = $\frac{\sqrt[]{25}}{\sqrt[]{34}}$
⇔`sin∝` = $\frac{5}{\sqrt[]{34}}$
⇔`sin∝` = $\frac{5\sqrt[]{34}}{34}$
Vậy `sin∝` = $\frac{5\sqrt[]{34}}{34}$
`cos∝` = $\frac{3\sqrt[]{34}}{34}$
$tan ∝$ = `\frac{5}{3}`
$#chucbanhoctotnhe;333$
