Soru

Zorluk: KolayOperations with Variable Exponents

If the equation y8⋅yk=y15y^8 \cdot y^k = y^{15} is true for all non-zero values of yy, what is the value of kk?

Cevap: 7 / seven

Cevap

7
The correct value of kk is 77 because applying the product rule of exponents gives y8⋅y7=y8+7=y15y^8 \cdot y^7 = y^{8+7} = y^{15}.

Adım Adım Çözüm

1
Apply the product rule for exponents to the left side of the equation.
y8⋅yk=y8+ky^8 \cdot y^k = y^{8+k}
When multiplying exponential expressions with the same base, the exponents are added.
2
Set the exponent of the simplified left side equal to the exponent of the right side.
8+k=158 + k = 15
Since the bases are equal and non-zero, their exponents must be equal.
3
Solve the linear equation for kk.
k=7k = 7
Subtracting 8 from both sides of the equation isolates the variable kk.

Anahtar Kavram

Product Rule for Exponents
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