स्पष्टीकरणासह प्रश्‍नसंच -3 - Maths & Resoning

1) \[3^{4-5x}\times 3^{5x-4}= ?\]

    Explanation:\[3^{4-5x+5x-4}= 3^{0}=1\](पाया समान म्‍हणून घातांकाची बेरीज)


    2) \[37=3^{x}+3^{y}+3^{z}\: \: \: , \: x+y+z=?\]

      Explanation: यामध्‍ये x, y, z च्‍या किमती अशा टाका की 3 चा तेवढ्या वेळा गुणाकार करून बेरीज केल्‍यास ती 37 येईल.
      \[3^{x}+3^{y}+3^{z}\: \: = 3^{3}+3^{2}+3^{0}=?\] = 27 + 9 + 1 = 37
      x + y + z = 3 + 2 + 0 = 5


      3) \[5^{6x+8}\div 5^{4x-5}=5^{21}\]

      Explanation: यात भागाकार आहे म्‍हणून वजाबाकी करावे.
      6x + 8 + (4x – 5) = 21
      6x + 8 – 4x + 5 = 21
      2x + 13 = 21
      2x = 21 – 13
      2x = 8
      x = 4


      4) \[\left ( \frac{15}{21} \right )^{12}\times \left ( \frac{15}{21} \right )^{14}\times \left ( \frac{21}{15} \right )^{26}\]

      Explanation: \[\left ( \frac{15}{21} \right )^{12}\times \left ( \frac{15}{21} \right )^{14}\times \left ( \frac{21}{15} \right )^{-26}\: \\=\left ( \frac{15}{21}\right )^{12+14-26}\\\left ( \frac{12}{21} \right )^{0}=1\]


      5) \[15^{3}\times \left ( 13^{3} \right )^{2}\times \left [ \left ( 15^{3} \right )^{2} \right ]^{2}=15^{m+8}\]

        Explanation: \[15^{3}\times 15^{6}\times 15^{12}=15^{m+8}\] \[m+8=21 \: \: 15^{21}=15^{m+8}\] m = 21 – 8
        m = 13


        6) \[\frac{10^{0}+15^{0}+20^{0}}{10^{0}\times 15^{0}\times 20^{0}}=?\]

          Explanation: \[\frac{1+1+1}{1\times 1\times 1}=\frac{3}{1}=3\]


          7)\[\frac{5^{0}+6^{0}+7^{}}{5^{0}\times 6^{0}\times 7^{0}}=9^{x-3\: \: ,\: \: x=?}\\]\]

            Explanation: \[\frac{1+1+7}{1\times 1\times 1}=\frac{9}{1}=9^{x-3}\: \\\\: 9=9^{x-3}\]1 = x-3
            x =1 + 3 x = 4


            8) \[\sqrt{6^{3x-2}}=6^{2}\: \: ,\: \: x=?\]

              Explanation:दोन्‍ही बाजुंचा वर्ग करा\[\left ( \sqrt{6^{3x-2}} \right )^{2}= \left ( 6^{2} \right )^{2}\]\[6^{3x-2}=6^{4}\] 3x-2 = 4
              3x = 4 + 2
              3x = 6 x = 6/3
              x = 2


              9) \[\frac{6^{2}\times 36\times 6^{4}}{36^{2}\times 6}=6^{x+1}\: \: , x=?\]

              Explanation: \[\frac{6^{2}\times 6^{2}\times 6^{4}}{\left ( 6^{2} \right )^{2}\times 6}= \: \: \: \left (36=6^{2} \right )\] \[\frac{6^{8}}{6^{5}}\:=6^{x+1}\: \: \: \: \frac{6^{2}\times 6^{2}\times 6^{4}}{\left ( 6^{4} \right )\times 6}=6^{6x+1}\] \[6^{3}=6^{6x+1}\] 3 = x + 1 x = 3 – 1 x = 2


              10) \[\sqrt{256^{\frac{1}{2}}}= m\:, \: \:m=?\]

                Explanation: \[\sqrt{256^{\frac{1}{2}}}= (\frac{1}{2}=\] घातांक आहे वर्गमुळ)\[\sqrt{16}=4\]