## Maths Demo test for class 9

### Total Question: 15

 1. If $\sqrt{19-4\sqrt{x}}=\sqrt{12}-\sqrt{7},$ then x = __________ 84 28 21 1
 2. $\sqrt{12\sqrt{5}+2\sqrt{55}}=$ _______ $(\sqrt{11}+1)\sqrt[4]{5}$ $\sqrt[4]{5}(1+\sqrt{5})$ $\sqrt[4]{5}(\sqrt{11}+\sqrt{5})$ none of these
 3. If $\sqrt{23+x\sqrt{10}}=\sqrt{18}+\sqrt{5}$, then x = __________ 2 3 5 6
 4. If $x=5+2\sqrt{6}$, then $\dpi{100} \small \sqrt{\frac{x}{2}}-\frac{1}{\sqrt{2x}}=$ ___________ 1 2 3 4
 5. If x = 8 - $\dpi{100} \small \sqrt{60}$, then $\dpi{100} \small \frac{1}{2}\left [ \sqrt{x}+\frac{2}{\sqrt{x}} \right ]=$_______ $\dpi{100} \small \sqrt{5}$ $\dpi{100} \small \sqrt{3}$ $\dpi{100} \small 2\sqrt{5}$ $\dpi{100} \small 2\sqrt{3}$
 6. If $\dpi{100} \small x=\sqrt{7}-\sqrt{5},\ y=\sqrt{13}-\sqrt{11},$ then: x = y x > y x < y $\dpi{100} \small x\geq y$
 7. $\dpi{100} \small \sqrt[6]{4}+\sqrt[4]{6}=$________ $\dpi{100} \small \sqrt[12]{\frac{2}{27}}$ $\dpi{100} \small \sqrt[12]{27/2}$ $\dpi{100} \small \sqrt[6]{2/3}$ $\dpi{100} \small \sqrt[4]{3/2}$
 8. $\dpi{100} \small \frac{3+\sqrt{6}}{\sqrt{75}-\sqrt{48}-\sqrt{32}+\sqrt{50}}=$ ____________ $\dpi{100} \small \sqrt{2}$ $\dpi{100} \small \sqrt{3}$ $\dpi{100} \small \sqrt{3}+\sqrt{2}$ $\dpi{100} \small \sqrt{3}-\sqrt{2}$
 9. If $\dpi{100} \small \frac{1}{\sqrt{10}+\sqrt{14}+\sqrt{15}+\sqrt{21}}=\frac{\sqrt{10}-\sqrt{14}-\sqrt{15}+\sqrt{21}}{k}$, then: k = 1/2 1 = k/2 1 = 2/k None
 10. If $\dpi{100} \small \sqrt{\frac{6+2\sqrt{3}}{33-19\sqrt{3}}}=a+b\sqrt{3},$ then a + b = ________ 6 8 10 12
 11. $\dpi{100} \small \sqrt{11}-\sqrt{10},$  $\dpi{100} \small \sqrt{12}-\sqrt{11}$ < > = cannot be determined
 12. If $\dpi{100} \small x=\sqrt{2}+1,\ y=\sqrt{17}-\sqrt{2},$ then _____ x < y x > y x = y None
 13. If $\dpi{100} \small x=\sqrt{\frac{7+4\sqrt{3}}{7-4\sqrt{3}}},$ then $\dpi{100} \small x^{2}(x-14)^{2}=$ __________ 1 -1 2 -2
 14. If $\dpi{100} \small \frac{4+3\sqrt{3}}{\sqrt{7+4\sqrt{3}}}=a+\sqrt{b},$ then (a, b) = _________ (12, -1) (1, 12) (-1, 12) (-12, 1)
 15. If $\dpi{100} \small a=\sqrt{14}+\sqrt{18},\ b=\sqrt{15}+\sqrt{17},$ then: a > b a < b a = b a = 1.5b