State whether the following are true or false. Justify your answer.

$(i)$ $\cos A$ is the abbreviation used for the cosecant of angle $A$

$(ii)$ cot $A$ is the product of cot and $A$.

$(iii)$ $\sin \theta=\frac{4}{3}$ for some angle $\theta$.

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$(iii)$ Abbreviation used for cosecant of angle $A$ is cosec $A$. And $\cos A$ is the abbreviation used for cosine of angle $A$

Hence, the given statement is false.

$(iv)$ cot $A$ is not the product of cot and $A$. It is the cotangent of $\angle A$.

Hence, the given statement is false.

$(v)$ $\sin \theta=\frac{4}{3}$

We know that in a right-angled triangle,

$\sin \theta=\frac{\text { Side opposite to } \angle \theta}{\text { Hypotenuse }}$

In a right-angled triangle, hypotenuse is always greater than the remaining two sides. Therefore, such value of $\sin \theta$ is not possible.

Hence, the given statement is false

Similar Questions

Show that:

$(i)$ $\tan 48^{\circ} \tan 23^{\circ} \tan 42^{\circ} \tan 67^{\circ}=1$

$(ii)$ $\cos 38^{\circ} \cos 52^{\circ}-\sin 38^{\circ} \sin 52^{\circ}=0$

$\frac{1+\tan ^{2} A}{1+\cot ^{2} A}=........$

If $\tan 2 A=\cot \left(A-18^{\circ}\right),$ where $2 A$ is an acute angle, find the value of $A .$ (in $^{\circ}$)

$9 \sec ^{2} A-9 \tan ^{2} A=..........$

$\sin 2 A=2 \sin A$ is true when $A=$