1. Let $a \in R$. If the function $y=f(x)$ is symmetric to $y=10^{x}+3$ with respect to the line $y=x$, and $y=f(x)$ intersects with $y=$ $\lg \left(x^{2}-x+a\right)$, then the range of values for $a$ is $\qquad$
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=, 1 . a3)$, and the equation $x^{2}-x+a=x-3$ has a root $x$ greater than 3. Therefore, the range of values for $a$ is the range of the function $a=-x^{2}+2x-3=-(x-1)^{2}-2$ $(x>3)$. Hence, $a<-6$ is the solution. (Please note the equivalent transformation)
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