Maths

The function $f(x)=\left\{\begin{array}{c}\frac{x^{2}}{a}, \text { if } 0 \leq x<1 \\ a, \text { if } 1 \leq x<\sqrt{2} \\ \frac{2 b^{2}-4 b}{x^{2}}, \text { if } \sqrt{2} \leq x<\infty\end{array}\right.$ Is continuous on $[0, \infty)$. Find the most suitable values of $a$ and $b$.

A real function f is said to be continuous at x = c, where c is any point in the domain of f if h is a very small positive number. i.e. left hand limit as x → c (LHL) = right hand limit as x → c...

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In the following, determine the value(s) of constant(s) involved in the definition so that the given function is continuous: (iii) $f(x)=\left\{\begin{array}{c}k\left(x^{2}+3 x\right) \text { if } x<0 \\ \cos 2 x, \text { if } x \geq 0\end{array}\right.$ (i v) $f(x)=\left\{\begin{array}{c}2 \text { if } x \leq 3 \\ a x+b, \text { if } 3

(iii) A real function f is said to be continuous at x = c, where c is any point in the domain of f if h is a very small positive number. i.e. left hand limit as x → c (LHL) = right hand limit as x →...

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In the following, determine the value(s) of constant(s) involved in the definition so that the given function is continuous: (i) $f(x)=\left\{\begin{array}{cc}\frac{\sin 2 x}{5 x} \text { if } x \neq 0 \\ 3 k, \quad i f x=0\end{array}\right.$ (ii) $f(x)=\left\{\begin{array}{l}k x+5 \text { if } x \leq 2 \\ x-1, \text { if } x>2\end{array}\right.$

(i) A real function f is said to be continuous at x = c, where c is any point in the domain of f if h is a very small positive number. i.e. left hand limit as x → c (LHL) = right hand limit as x → c...

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Find the points of discontinuity, if any, of the following functions: (x i) $f(x)=\left\{\begin{array}{c}2 x, \text { if } x<0 \\ 0, \text { if } 0 \leq x \leq 1 \\ 4 x, \text { if } x>1\end{array}\right.$ (x i i) $f(x)=\left\{\begin{array}{c}\sin x-\cos x, \text { if } x \neq 0 \\ -1, \text { if } x=0\end{array}\right.$

(xi) A real function f is said to be continuous at x = c, where c is any point in the domain of f if h is a very small positive number. i.e. left hand limit as x → c (LHL) = right hand limit as x →...

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Find the points of discontinuity, if any, of the following functions: (i x) $f(x)=\left\{\begin{array}{c}|x|+3, \text { if } x \leq-3 \\ -2 x, \text { if }-33\end{array}\right.$ (x) $f(x)=\left\{\begin{array}{c}x^{10}-1, \text { if } x \leq 1 \\ x^{2}, \text { if } x>1\end{array}\right.$

(ix) A real function f is said to be continuous at x = c, where c is any point in the domain of f if h is a very small positive number. i.e. left hand limit as x → c (LHL) = right hand limit as x →...

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Find the points of discontinuity, if any, of the following functions: $(v i i) f(x)=\left\{\begin{array}{c}\frac{e^{x}-1}{\log _{c}(1+2 x)}, \text { if } x \neq 0 \\ 7, \text { if } x=0\end{array}\right.$ (viii) $f(x)=\left\{\begin{array}{c}|x-3|, \text { if } x \geq 1 \\ \frac{x^{2}}{4}-\frac{3 x}{2}+\frac{13}{4}, \text { if } x<1\end{array}\right.$

((vii) A real function f is said to be continuous at x = c, where c is any point in the domain of f if h is a very small positive number. i.e. left hand limit as x → c (LHL) = right hand limit as x...

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Find the points of discontinuity, if any, of the following functions: (i) $f(x)=\left\{\begin{array}{c}x^{3}-x^{2}+2 x-2, \text { if } x \neq 1 \\ 4, \text { if } x=1\end{array}\right.$ (ii) $f(x)=\left\{\begin{array}{l}\frac{x^{4}-16}{x-2}, \text { if } x \neq 2 \\ 16, \text { if } x=2\end{array}\right.$

(i) A real function f is said to be continuous at x = c, where c is any point in the domain of f if h is a very small positive number. i.e. left hand limit as x → c (LHL) = right hand limit as x → c...

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38. Prove that:(iii)$$$\sqrt{\frac{(1+\cos \theta )}{(1-\cos \theta )}}+\sqrt{\frac{(1-\cos \theta )}{(1+\cos \theta )}}=2\cos ec\theta $(iv) $\frac{\sec \theta -1}{\sec \theta -1}={{\left( \frac{\sin \theta }{1+\cos \theta } \right)}^{2}}$

Solving L.H.S and dividing the numerator and denominator with its respective conjugates, we have $=\sqrt{\frac{(1-\cos \theta )(1-\cos \theta )}{(1+\cos \theta )(1-\cos \theta...

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38. Prove that: (i)$\sqrt{\frac{(\sec \theta -1)}{(\sec \theta +1}}+\sqrt{\frac{(\sec \theta +1)}{(\sec \theta -1)}}=2\cos ec\theta $(ii)$\sqrt{\frac{(1+\sin \theta )}{(1-\sin \theta )}}+\sqrt{\frac{(1\sin \theta )}{(1+\sin \theta )}}=2\sec \theta $

Solving L.H.S and divide the numerator and denominator with its respective conjugates, we have $=\sqrt{\frac{(\sec \theta -1)(\sec \theta -1)}{(\sec \theta +1)(\sec \theta -1)}}+\sqrt{\frac{(\sec...

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Find the adjoint of each of the following matrices:
(i) $\left[\begin{array}{cc}-3 & 5 \\ 2 & 4\end{array}\right]$
(ii) $\left[\begin{array}{ll}a & b \\ c & d\end{array}\right]$ Verify that $(\operatorname{adj} A) A=|A| I=A(\operatorname{adj} A)$ for the above matrices.

Solution: (i) Suppose $A=\left[\begin{array}{cc}-3 & 5 \\ 2 & 4\end{array}\right]$ Cofactors of $A$ are $C_{11}=4$ $C_{12}=-2$ $C_{21}=-5$ $C_{22}=-3$ Since, adj...

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