1
NDA 2019 Paper 2
MCQ (Single Correct Answer)
+2.5
-0.83
If $${x^{{{\log }_7}x}} > 7$$ where x > 0, then which one of the following is correct?
A
$$x \in (0,\infty )$$
B
$$x \in \left( {{1 \over 7},7} \right)$$
C
$$x \in \left( {0,{1 \over 7}} \right) \cup (7,\infty )$$
D
$$x \in \left( {{1 \over 7},\infty } \right)$$
2
NDA Mathematics 14th September 2025
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language
For the following two (02) items:
Let $\alpha$ and $\beta $ be the roots of the quadratic equation
$(x^{2}+(\log _{0.5}(\alpha ^{2}))x+(\log _{0.5}(\alpha ^{2}))^{4}=0$
where $a ^ 2 \ne1$ and $\log _{0.5}(\alpha ^{2})>0$ Further, $\beta ^{2}=\alpha (\log _{\alpha ^{2}}(0.5))$
 
What is ẞ equal to?
1
$\log _{a^{2}}(0.5)$
2
$\log _{0.5}(a^{2})$
3
$2(\log _{a^{2}}(0.5))$
4
$2\log _{0.5}(a^{2})$
3
NDA Mathematics 14th September 2025
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language
For the following two (02) items:
Let $p=\sum_{j=1}^{n}\log_{10}2^{j} and q=\sum_{j=1}^{n}\log_{10}5^{j}$
If p + q = 66 then which one of the following is correct?
1
n < 7
2
7 < n < 9
3
9 < n < 12
4
n > 12
4
NDA Mathematics 14th September 2025
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language
For the following two (02) items:
Let $p=\sum_{j=1}^{n}\log_{10}2^{j} and q=\sum_{j=1}^{n}\log_{10}5^{j}$
If p + q = 15 then what is equal to? q - p
1
$\log_{10} 2 \cdot 5$
2
$5\log_{10} 2 \cdot 5$
3
$10\log_{10} 2 \cdot 5$
4
$15\log_{10} 2 \cdot 5$